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How to do Keyword Research (for FREE) using Google
by Josh | Jan 19, 2022 | Web Design Tutorial | 2 comments
There are a lot of great keyword research tools out there but wouldn’t it be nice to be able to do some basic research for free? Good news! You can do so using good old trusty Google. In this tutorial, I’ll show you how!
There are many other tactics, strategies and methods for both free and paid keyword research but these methods are the easiest to learn and implement.
Here are my top 5 methods for using Google for free keyword research:
We’ll start with what is probably the most obvious method…
That’s right, typing your keyword or key phrase into Google and seeing what it suggests is the first method and easiest way to do basic and free, keyword research.
![google keyword research free](https://joshhall.co/wp-content/uploads/2022/01/free-keyword-research-with-google-josh-hall-method-1-google-search-suggestions-1024x573.jpg)
Using Google for free keyword research – Method 1 using the search bar suggestions
![google keyword research free](https://joshhall.co/wp-content/uploads/2022/01/free-keyword-research-with-google-josh-hall-method-2-detailed-alphabetical-google-search-1024x574.jpg)
Using Google for free keyword research – Method 2 detailed alphabetical suggestions in search bar
![google keyword research free](https://joshhall.co/wp-content/uploads/2022/01/free-keyword-research-with-google-josh-hall-method-3-people-also-ask-section-1024x575.jpg)
Using Google for free keyword research – Method 3 “People also ask” section
![google keyword research free](https://joshhall.co/wp-content/uploads/2022/01/free-keyword-research-with-google-josh-hall-method-4-related-searches-1024x513.jpg)
Using Google for free keyword research – Method 4 “Related searches” section
![google keyword research free](https://joshhall.co/wp-content/uploads/2022/01/free-keyword-research-with-google-josh-hall-method-5-suggested-videos-1024x575.jpg)
Using Google for free keyword research – Method 5 suggested videos
So there you go! My top 5 methods for using Google for free keyword research.
I hope this has helped give you some ideas of how to use Google the next time you’re looking for the best keywords to optimize your content for.
Again, there are a plethora of tools (both free and paid) that can assist with this and I’m sure there are other free strategies as well so if you know of one, feel free to drop a comment below!
Related articles, videos or podcasts:
- Podcast 107 – How to do free keyword research with my personal SEO guru Michelle Bourbonneire
- Podcast 162 – How Google algorithm updates can effect your SEO strategy with Julian Goldie
And for those of you ready to learn a little more about SEO, be sure to sign up for my free SEO Masterclass “A Beginners Guide to SEO for Web Designers” below!
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Great article Josh. In addition to what I call “mining the SERPs” which is basically what you talked about here, I also love and recommend two other resources for keyword research … LongTailPro and Ubersuggest.
My affiliate link for LTP is https://www.premiumwebdesign.com/longtailpro/ .
Keep up the great work!
![google keyword research free google keyword research free](https://joshhall.co/wp-content/uploads/2020/08/josh-hall-email-sig-fall-2019-100x100.jpg)
Great additional suggestions, Glennette! Haven’t heard of or used LTP but heard good things about Ubersuggest. Thanks!
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Find Great Long Tail Keywords With The Best Free SEO Tool
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What is Google Keyword Planner?
There are many ways to drive more traffic to your website, and using an SEO tool is one of them.
If you are looking to optimize your page or website and improve overall keyword rankings, you should use a reliable SEO tool for Google. Since the majority of searchers are done on Google - the largest search engine in the world - it is best to focus your effort on that platform.
By using an SEO tool for Google, you will be able to perform keyword research easier and more efficiently. You will find relevant and highly searched keywords to include in your page's meta tags and improve your website ranking for better SEO marketing.
![google keyword research free google keyword research free](https://i.ytimg.com/vi/h35okcHNmtk/maxresdefault.jpg)
What are SEO Tools?
An SEO tool can be used for many things - keyword research, keyword analysis , improving website ranking, search engine marketing, and many more. Among all its function, the most important is its ability to generate relevant keywords.
Keywords are the most important part of SEO optimization and the first step towards improving a website's ranking to attract more traffic. In order to find the most relevant search terms - be it highly searched focus keywords or long tail keywords with high conversion rate potential - you will need a reliable SEO tool.
There are many product types of SEO tools - some are expensive, while others can be used for free like Keyword Tool. For additional functionality and more keyword data, there is also an option to purchase Keyword Tool Pro.
You may have come across SEO tools group buy offers. Try to avoid those services as they obtain accounts and login information from various SEO products in a questionable manner. It is also unreliable and often has limited usage.
SEO is hard work but it pays off well in the end. It is best to go with a reputable SEO brand to ensure you get the most out of the product and maximize the output for your work.
Improve Your Google SEO and Increase Website Ranking with Keyword Tool
An SEO tool for Google is, in essence, a keyword tool. It allows you to perform keyword research, which is the foundation of SEO, and the first step towards optimizing a page or website by using relevant keywords.
To do that, you can use a free SEO tool like Keyword Tool. A quick search can generate thousands of focus keywords and long tail keywords.
The paid version Keyword Tool Pro provides a lot of useful and valuable information, like search volume, trends, cost-per-click, and competition level. It is only by knowing these key data that you will be able to properly optimize your page or website to improve its SEO.
Keyword research can often be tedious and time-consuming, which is why having a good SEO tool like Keyword Tool can help you gain an advantage over your competitors. It is no surprise then that thousands of internet marketing professionals use Keyword Tool in their daily workflow.
![google keyword research free google keyword research free](https://i.ytimg.com/vi/CBVOqHLUu1o/maxresdefault.jpg)
Find Long Tail Keywords with an SEO Tool
Will you get more traffic to your website when you use high-volume focus keywords? If done right, most likely you will. But what about long tail keywords?
Many people often overlook the power of using long tail keywords. They usually have much lower search volumes. Though when compared to shorter focus keywords, long tail keywords have far better conversion rates.
When you include long tail keywords in your content, it will draw searchers who already have an intention to purchase a product or sign up in an email list. Longer keywords are more specific, hence it accurately reflects the search intent of users.
It is for this reason that long tail keywords often receive better click through rates compared to shorter focus keywords. By using a good SEO tool for Google, you will be able to find and generate long tail keywords for your content.
They are best used for user acquisition, be it for an e-commerce website, email subscription list, affiliate website, or others.
How Keyword Tool Can Help Improve SEO and Search Engine Marketing
Some might confuse between search engine optimization (SEO) and search engine marketing (SEM) - SEO is the exercise of optimizing a page or website to attract organic traffic, while SEM involves paid search campaigns like Google Ads or Bing Ads .
Keyword Tool can be incredibly useful to find highly searched keywords to improve SEO. At the same time, it can also be used to source for relevant search terms to optimize your search ads .
When a Google Ads campaign uses keywords that are highly searched and relevant to the brand or business, it will attract more clicks on the search ads. That will then result in a higher click-through-rate (CTR). With a CTR, it increases the potential of conversions and thus lowers the cost-per-click (CPC) or the cost of customer acquisition.
At the same time, a good keyword tool will be able to show the CPC for the generated keywords. With that data, SEM professionals or Google Ads campaign managers will be able to find more cost-efficient keywords to use for their search ad campaigns.
Why Keyword Tool is the Best SEO Tool You Can Find
For most SEO professionals or marketers, focusing on optimizing SEO for Google is a crucial part of the job. At the same time, SEO can also prove to be valuable for small business owners, affiliate marketers, content creators or e-commerce entrepreneurs. It is by far the most cost-effective marketing channel for lead generation and user acquisition.
Keyword Tool is an ideal tool for keyword research for Google, but it also has powerful keyword and hashtag search features for YouTube, Amazon, Instagram, eBay, App Store, and Twitter. By pulling real-time data from the different platform's Autocomplete and Google search engine, Keyword Tool is able to generate thousands of keywords and hashtags within seconds.
Whether you are a content creator looking for YouTube tags or an Amazon FBA seller sourcing for keywords to optimize product listings, you can find them all on Keyword Tool.
Frequently Asked Questions
⭐ why do i need seo tools, ⭐ what are the essential tools for seo, ⭐ where to find free seo tools, ⭐ can i trust the data provided by seo tools.
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15 Free Keyword Research Tools For 2023
There are a variety of free keyword research tools you can use if you don't have the budget for a premium paid keyword tool
![google keyword research free 15 Free Keyword Research Tools For 2023](https://www.searchenginejournal.com/wp-content/uploads/2023/02/keyword-research-tools-6411cbc3d7efa-sej.jpg)
One of the biggest opportunities of search engine optimization (SEO) is performing keyword research and designing a content plan supported by the results of your research.
Keyword research helps you to:
- Understand your target audience’s search intent .
- Gather information about related topics and questions searchers often ask.
- Monitor the current competitive landscape for your topic.
All of these things can affect your resulting content quality.
Keyword research is crucial in shaping your article’s structure and creating something that meets your customers’ needs.
But not all website owners do it. Many think it requires complicated or paid keyword research tools — but that’s not necessarily true.
To show you don’t need to commit to premium plans to get used to these tools, we’ve listed the 15 best free keyword research tools below.
1. GetKeywords
![google keyword research free Best free keyword research tools: GetKeywords.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/getkeywords-63f6a37e25d71-sej.png)
GetKeywords is one of the best free keyword research tools for local SEO .
It supports keyword metrics for over 100,000 locations with filters that narrow down search results to countries, provinces, and cities.
It also has metrics that are usually unavailable in free keyword tools and supports up to 45 languages.
On top of that, GetKeywords shares real-time data, unlike many other keyword tools that use stored data.
Key Features :
- Real-time data analysis.
- Shares your audience’s preferred devices and competitors’ traffic sources.
- Provides global search.
Best Keyword Research Tool For : Local SEO.
Pricing : Free plan with unlimited searches. Premium plans for advanced features like SEO difficulty and competitor keywords start at $24/month when billed annually.
![google keyword research free Best free keyword research tools: Sonar.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/sonar-february-2023-63f6a47847332-sej.png)
If you need a basic keyword tool for Amazon keyword research , Sonar comes highly recommended.
Sonar has a database of over 180 million keywords in multiple languages, updated in real-time.
Its reverse Amazon Standard Identification Number (ASIN) lookup lets you identify and track competitors’ keywords.
Enter the competitor’s ASIN, and Sonar gives you the list of keywords the product is ranking for.
However, that’s the extent of its features.
- 180+ million keywords in multiple languages.
- Reverse ASIN lookup.
- No need to create a user account.
Best Keyword Research Tool For : Amazon sellers.
Pricing : Free.
3. QuestionDB
![google keyword research free Best free keyword research tools: QuestionDB.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/questiondb-february-2023-63f6a52b837c1-sej-e1677560086856.png)
Need new blog topic ideas? QuestionDB is one of the best free keyword research tools for that.
When you enter a seed keyword, QuestionDB generates common questions people ask on popular platforms such as Reddit, Stack Exchange, and Quora.
You gain insights into how customers think, generating relevant keywords based on what people are searching for.
- Gain insights into questions people commonly ask about a topic.
- Generate relevant content ideas based on what people search for.
- Multiple data sources (Reddit, Stack Exchange, Quora).
Best Keyword Research Tool For : Creating informative blog posts.
Pricing : Free with limited features. Premium plans start at $12.50/month when billed annually.
4. Ryan Robinson’s Keyword Tool
![google keyword research free Best free keyword research tools: Ryan Robinson’s Keyword Tool.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/ryrob-free-keyword-research-tool-63f6a5ebcd53a-sej.png)
New or smaller websites should target keywords with medium search volume and low keyword difficulty.
Though many free keyword research tools don’t highlight this data, Ryan Robinson’s free AI-powered keyword research tool does.
Ryan Robinson is a professional blogger and as head of content at CRM provider Close, Ryan is familiar with content marketing pain points.
- Focuses on essential metrics: estimated search volume and suggested blog topics.
- Accompanied by a useful tutorial explaining the importance of keyword research to show you how to best use the tool.
- Get country-specific search data.
Best Keyword Research Tool For : Finding untapped phrases surrounding a keyword.
5. Keyword Tool Dominator
![google keyword research free Best free keyword research tools: Keyword Tool Dominator.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/keyword-tool-dominator-february-2023-63f6a6a085298-sej.png)
If you’re a multichannel marketer or work in the ecommerce space, Keyword Tool Dominator is the tool for you.
It sources keywords from nine major retail databases (Amazon, Bing, eBay, Etsy, Google, Google Shopping, Home Depot, Walmart, and YouTube) for the best long-tail keywords .
However, the free plan limits you to two keyword searches daily and doesn’t offer keyword analysis.
- Unlimited real-time keyword searches (premium plans only).
- Unlimited keyword suggestions – including long-tail keywords.
- Export reports.
Best Keyword Research Tool For : Multichannel marketers.
Pricing : Free with limited features. Lifetime unlimited access to tools starts at $49, a one-time payment for each tool. The bundle that includes 6 keyword tools starts at $99.
6. Google Autocomplete
![google keyword research free Best free keyword research tools: Google Search data.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/google-search-data-63f6a6fde3848-sej.png)
It depends on your level of awareness of the best free keyword research tools.
Google Search data may seem basic, but it offers a wealth of information you can use for keyword research, intent exploration, and content creation .
- Autocomplete : Shares search suggestions that include various long-tail keyword phrases that are variations of your primary keyword.
- People Also Ask : Shares questions that searchers ask related to your keyword. “People Also Ask” provides great opportunities for subheadings and featured snippets.
- Related Searches : Displays searches that don’t necessarily involve the same exact words as the primary keyword you typed in but are semantically related. These searches represent related topics that may make sense to bring up in your article based on what users are interested in learning and suggestions for future related topics to write.
![google keyword research free Screenshot of related searches section of search query “best free keyword research tools,” Google, February 2023.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/google-related-searches-63f6a754ede39-sej.png)
- Things To Know : Google has been testing a search engine results page (SERP) feature that displays and arranges information about a topic into different categories. Clicking on the category will show a featured snippet about the topic.
![google keyword research free Screenshot of Google’s Things to know section for the search query “programmatic advertisement”, Google, February 2023.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/google-search-things-to-know-section-63f6a7c4b1bb7-sej.png)
Pricing: Free.
7. Keyword Tool
![google keyword research free Best free keyword research tools: KeywordTool.io.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/keywordtool-february-2023-63f6a831ac7da-sej.png)
Keyword Tool is a great alternative to Google Keyword Planner as it focuses on sources other than Google.
It uses data from various search engines, ecommerce websites, and social media platforms, such as Bing, YouTube, Amazon, eBay, Instagram, and Pinterest, to generate long-tail keywords that aren’t visible on Google’s Keyword Planner.
Choose the website and country you want to view data from, and Keyword Tool will generate a list of suggestions and questions based on autocomplete data from those sources.
- Generates up to 750+ long-tail keyword suggestions for every search term.
- Multiple data source inputs.
Best Keyword Research Tool For : Multichannel keyword research.
Pricing : Free plan available. The premium version starts at $69/month when billed annually.
![google keyword research free Best free keyword research tools: Glimpse.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/glimpse-february-2023-63f6a8e316942-sej.png)
Many SEOs use Google Trends to find new keywords they can rank for.
However, it’s only good for finding trends you’re already aware of – not predicting future trends.
Glimpse closes that gap by identifying upcoming search trends that are useful for people in the digital PR or ecommerce space.
Glimpse is a free Chrome extension with a limitation of 10 free credits a month.
- Long-tail search data.
- Set Google Trend alerts to alert you when a topic starts trending.
- A database of thousands of trends. It checks for popular and high-growth topics from websites outside Google, including Pinterest, Amazon, TikTok, and YouTube, so you can find business ideas before they become mainstream.
Best Keyword Research Tool For : Finding keyword trends.
9. Keywords Everywhere
![google keyword research free Best free keyword research tools: Keywords Everywhere.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/keywords-everywhere-february-2023-63f6a946e97cd-sej.png)
Keywords Everywhere is a freemium browser add-on for Firefox and Chrome.
It gathers keyword suggestions from over 15 of the most popular keyword tools, such as AnswerThePublic, Google Search, and Ubersuggest.
From there, it displays related keywords, keyword trends, and terms your competitors are ranking for.
- Collates data from popular keyword research tools like Ubersuggest, AnswerThePublic, Google Search, Google Analytics, Google Search Console, and Moz Open Site Explorer.
- Displays YouTube and Google Trends from 2004 onwards.
- Shares YouTube and Google traffic metrics (no volume data for the free version).
- Find keywords your competitors rank for (no volume data for the free version).
Best Keyword Research Tool For : Keyword research within search.
Pricing : Free with limited features. The Premium version uses the pay-as-you-go model. You can buy 100,000 credits (one credit = research data for one keyword) for as low as $10.
10. AlsoAsked
![google keyword research free Best free keyword research tools: AlsoAsked.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/alsoasked-february-2023-63f6a9a8ebe47-sej.png)
AlsoAsked is a freemium keyword research tool centered around Google’s “People Also Ask” (PAA) data.
When you enter a seed keyword, AlsoAsked suggests relationships between topics and illustrates them with a branching diagram that you can download as .CSV or .PNG files.
![google keyword research free Screenshot of questions generated from the query “best free keyword research tools,” AlsoAsked, February 2023.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/alsoasked-grouped-keywords-63f6aa0614adf-sej.png)
However, AnswerThePublic focuses specifically on autocomplete data.
- Identify related keywords.
- Visualize keyword relationships.
- Export keyword data as .CSV or .PNG files.
Best Keyword Research Tool For : Content ideation and finding related questions people ask.
Pricing : Limited free trial available. Starts at $15/month.
11. Keyword Surfer
![google keyword research free Best free keyword research tools: Keyword Surfer.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/keyword-surfer-february-2023-63f6aa6a4053b-sej.png)
If you’re a digital marketer, Surfer’s free Chrome extension is one of the best free keyword research tools you can use.
Surfer’s free Chrome extension lets you see different keyword metrics without leaving the Google Search page. These metrics, which are tailored to each country, include the following:
- Estimated monthly search volume.
- Cost-per-click (CPC).
- Number of times the keyword is used on the page.
- Word count for competitors’ pages.
- Related keywords and those keywords’ overlap score and search volume.
The features offered are very powerful for a free tool – it’s no wonder it’s so popular.
- Dataset from 70 countries.
- Monitor and keep keywords you don’t want to forget (using the Collections folder).
- Export files using CSV.
Best Keyword Research Tool For : Finding overlapping keywords.
12. Keyworddit
![google keyword research free Best free keyword research tools: Keyworddit.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/keyworddit.-february-2023-63f6aab17a950-sej.png)
Reddit is a goldmine for keyword ideas.
The website recognizes that and built Keyworddit – one of the best free keyword research tools to find keywords based on your target audience’s questions.
Keyworddit goes through subreddits (communities) representing your target audience’s characteristics.
With a specific niche in mind, run the subreddit names through Keyworddit. It will extract keywords that represent what engaged users frequently talk about.
Note that search volume is based on GrepWords (a keyword and SERP data platform), not Reddit search data.
- Identify the most popular topics on Reddit.
- Understand the specific topics that engage your audience.
- Includes a “Context” link that opens a Google search of the subreddit and keyword to see how people are using it on Reddit.
Best Keyword Research Tool For : Brands that want to market on Reddit.
![google keyword research free Best free keyword research tools: Jaaxy.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/jaaxy-63f6aafe53515-sej.png)
Jaaxy is one of the best free SEO keyword research tools for affiliate marketers.
Like other tools, it shows:
- Related keywords.
- The average number of monthly searches for each keyword.
- Estimated traffic to your website if you rank on page one for that keyword.
- The number of competing websites for that specific keyword.
What makes it different is that it shows affiliate programs you can join.
Jaaxy also has a keyword quality indicator, which tells you whether your keyword is great (green), normal (orange), or poor (red).
- Lists relevant affiliate programs to join based on your search input (sourced from Commission Junction, LinkShare, Digital River, and ClickBank).
- Track keywords and determine where they rank using the built-in SiteRank analysis tool.
- Results are exportable in CSV format.
Best Keyword Research Tool For : Affiliate marketers.
Pricing : Free with limited features. The Premium version starts at $49/month.
14. TagCrowd
![google keyword research free Best free keyword research tools: TagCrowd.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/tagcrowd-february-2023-63f6ab6121953-sej.png)
TagCrowd helps you visualize keyword frequency – or the number of times a keyword appears on a page – by creating word/text/tag clouds.
You can use it to determine a topic’s optimum keyword frequency or check which keywords competitors use in their content.
Note that you can get more detailed data with premium SEO tools like Semrush and Ahrefs Keywords Explorer .
- Simple user interface.
- Customized HTML clouds for embedding.
- Multi-language support.
- Upload a file.
- Enter the webpage URL.
- Paste page text.
Best Keyword Research Tool For : Visualizing keyword frequency.
![google keyword research free Best free keyword research tools: Soovle.](https://www.searchenginejournal.com/wp-content/uploads/2023/02/soovle-february-2023-63f6abb951902-sej.png)
Soovle functions as both a keyword generator and research tool, helping users find keywords across multiple popular websites such as YouTube, eBay, Amazon, and Wikipedia.
Users can toggle between different search engines to tailor their output.
- Generates suggestions relevant to each platform.
- Unlimited searches.
- Idea generator.
Best Keyword Research Tool For : Finding keyword ideas on search engines besides Google.
Final Thoughts: 15 Best Free Keyword Research Tools For 2023
An effective SEO strategy begins with keyword research. It helps you:
- Find the right keywords that align with your website’s objectives and intent.
- Determine topics your searchers are interested in.
- Gather information about competitors.
The best free keyword research tools on this list will make these tasks (and more) easier.
Did we miss any of the best free keyword research tools you think should be a part of this list?
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Maddy Osman is the author of “Writing for Humans and Robots: The New Rules of Content Style” (learn more: https://www.amazon.com/dp/B09X4NJ9H8). ...
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The Best Free Keyword Research Tools
Learn about the tools that can help you craft a successful SEO strategy—all at no cost.
![google keyword research free Keyword Research Tools-Hero illustration](https://eep.io/images/yzco4xsimv0y/4knlpJ0MnCTIZYkZ6GYYNZ/25af7e7492f1589909cbf22e47be909b/Keyword_Research_Tools-Hero_NEW_BACKGROUND.png?w=980&q=70)
Without keyword research tools, finding the right terms to incorporate into your blog or online store content to help it rank on search engine results pages (SERPs) would be like throwing darts in a dark room. Every once in a while, you would hit the target, but many darts would land on the floor.
Keyword research tools facilitate your SEO planning in multiple ways. They can help you generate keyword ideas, reveal how many people actively use a search term, identify trends, and show you how much competition you face to rank for a specific phrase.
Free keyword research tools
There are a surprising number of fantastic free tools you can use to gather vital information for marketing and SEO. Here are 12 free keyword research tools that are easy to use and full of valuable data.
Some are powerful keyword generators for Google and other search engines. Others provide targeted data for e-commerce websites like eBay, Etsy, and Amazon. The most comprehensive of these tools include essential SEO data like the monthly search volume and intensity of competition for your target terms.
Below are descriptions of what you can accomplish with each free keyword research tool, as well as their benefits and drawbacks. The tools covered are:
Keyword Surfer
Answerthepublic, keyword sheeter, ahrefs keyword generator, semrush keyword magic tool, ubersuggest, moz keyword explorer, keyword tool dominator, google trends.
![google keyword research free](https://eep.io/images/yzco4xsimv0y/3FPpsQSS893sXsbegjuGwE/e2194a554eb8d0317602df69381e64c2/Mailchimp_Content_Refresh_-35_Graphic_1.png?w=980&q=70)
Keyword generators for blog topic ideas
Keyword generators help you home in on what your potential customers want to know. They scrape search engines and question-and-answer databases to reveal new blog topics and keyword ideas.
Keyword Surfer is a newer tool that plugs right into the Chrome web browser. When it’s on, results automatically display on the right side of your results page each time you enter a search term.
The data delivered by Keyword Surfer includes:
- Keyword ideas with their volume
- Cost per click (CPC) for each search term
- Pages that rank for the term you entered
- Traffic to pages ranked 1 through 10 for that term
It’s a highly efficient keyword research tool and delivers results as you use your web browser. As a new tool, there may be some kinks to work out. Data delivered by the plugin can sometimes differ from data supplied by other Google search tools. However, it’s a fast and easy way to get content ideas.
AnswerThePublic is a great place to see raw search insights. After you enter your search term(s), it displays the questions people are asking related to that topic. The results are shown in a graphic display with all the who, what, where, when, why and other questions users ask.
It’s a powerful way to generate keyword ideas and see what your potential customers actually want to know. You can download the data as a graph or a list.
There is one con for this tool: With a limit of 3 free searches a day, you have to be thoughtful about each phrase you search.
Keyword Sheeter pulls autocomplete results from Google. It delivers real-time data on what people are typing into the search engine.
If you want to generate a long list of keyword ideas fast, Keyword Sheeter is an excellent choice. It pulls about 1,000 ideas per minute, and exporting your list is free.
It’s a simple and powerful resource to identify ideas for blog topics. However, the free features of Keyword Sheeter do not include search volume or data on how competitive it is to rank for a phrase.
Keyworddit mines Reddit for keywords. To use it, enter a specific subreddit with at least 10,000 subscribers and specify a timeframe. The tool searches through the titles and comments to extract up to 500 keywords with search volumes.
Due to the variety of answers within each subreddit, the relevance of the results may vary. There is an option to specify high relevance, which slows down the tool somewhat.
Keyworddit is not designed to replace other keyword research tools, but it can be an interesting complement to your existing strategy. Reddit is a popular site where people with specific interests take deep dives into a topic. It may reveal keyword phrases and blog topics you wouldn’t find using other search tools.
QuestionDB is an excellent blog topic idea generator. It pulls from several question-and-answer websites, including Reddit and Quora, to give you questions people are actively asking related to your keywords .
The free version of the tool allows unlimited searches without registering for an account. You can download your results with a single click.
You have the option to display the source link for each question. This allows you to review additional details about how people are framing their questions. You can also review the answers. QuestionDB also displays related topics mentioned in the questions.
The free account limits you to 50 results per query.
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Freemium keyword research tools for SEO analysis
A few of the premium paid websites offer free tools for limited use. You get the same outstanding services provided by the premium services for a limited number of searches or fewer features. Even so, they are comprehensive free keyword research tools.
Ahrefs Keyword Generator is one of the free tools offered by Ahrefs, which is a popular paid service. Enter any target keyword or phrase, and it will pull the top 100 keyword ideas from its database of over 8 billion keywords from more than 170 countries.
For each keyword phrase, the Keyword Generator displays:
- Search volume
- Keyword difficulty from 1 to 100
- How recently this result was updated
- A list of questions related to your search term
You can use this keyword research tool to identify long-tail keywords, target less competitive phrases, and isolate your search using geographic location or search engine.
It allows you to export your data by downloading your list of results. In addition to the Keyword Generator that pulls from Google, Ahrefs also has free Bing , YouTube , and Amazon tools.
While some freemium services include the SERP results inside the keyword search tool, Ahrefs provides their free SERP service on a separate page.
Ahrefs Keyword Generator is an efficient and valuable free tool that allows you to do unlimited searches without creating an account. However, unlike other tools, it does not allow you to download your results. And, because you don’t create an account with the free service, you have to prove you’re not a robot with every new search.
![google keyword research free](https://eep.io/images/yzco4xsimv0y/6PrzSskwExiEl8cFJGgbMZ/c7a7fb14271dd51d40424192f0a325c5/Mailchimp_Content_Refresh_-35_Graphic_2.png?w=980&q=70)
Semrush Keyword Magic Tool is one of several free tools offered by SEO giant Semrush. To access their free tools, create an account and select Skip Trial. You can always sign up for the paid service down the road if you’d like.
The Keyword Magic Tool gives you access to more than 20 billion keywords from over 120 geographical databases.
Free reports include:
- Monthly search volume
- Competitive density (competition among paid advertisers)
- Keyword difficulty (how difficult it would be to rank in Google’s top 20)
The Keyword Magic Tool also has some helpful sorting and organizing features. It allows you to sort keywords into topic-specific subgroups, apply smart filters to narrow or expand your search, and quickly export your findings. You can see related keywords by topic and semantically related keywords or by keywords with similar phrasing.
The free account limits you to 10 searches a day across all the complementary tools provided by Semrush.
Ubersuggest provides a wealth of information with its free version. When you enter a search term, it displays the search volume, SEO difficulty, paid difficulty, and CPC.
Immediately beneath that display, it identifies the number of backlinks you would need to rank on the first page of Google for that keyword phrase.
As you scroll down, you can view lists of keyword ideas and page content ideas.
The list of page content ideas displays related blog titles. At a glance, you can see how many people click on and share each article. You can export most of your data reports to CSV to save and sort. Ubersuggest provides a free Chrome extension to see data right on the SERP easily.
The free version limits your use to a single website and 3 keyword searches per day.
Moz Keyword Explorer is an attractive and well-laid-out keyword research tool. You can see monthly volume, organic difficulty, organic click-through rate (CTR), and a priority score for each search term.
The organic CTR displays how many people who use the term follow through and click on one of the results. The priority score aggregates the difficulty, opportunity, and volume to show you in a simple score how likely you are to rank for that keyword phrase.
Keyword Explorer delivers a long list of keyword suggestions for each term, with monthly search volume and relevancy.
The SERP analysis, also included with the free search results, gives you 10 specific pages that rank for your target keyword. You can see their title, URL, page authority, domain authority, number of backlinks to the page, and the number of backlinks to the root domain. It’s easy to download results into a spreadsheet.
Moz provides an excellent service. The downside is the free account limits you to 10 queries a month.
Keyword research tools for e-commerce, online sellers, and multichannel marketers
Most keyword tools focus on Google and other search engines. However, platforms like YouTube, Amazon, eBay, and Etsy have their own algorithms.
For e-commerce stores or sellers whose goals reach beyond ranking on Google and other search engines, tools like Keyword Tool Dominator and Soovle help you target the platforms you are using.
Soovle is great for e-commerce websites or marketers using multiple channels. It helps you find popular keywords across several megasites, including Amazon, Wikipedia, YouTube, and eBay.
Soovle works as a keyword research tool and a keyword generator. As you type in your target terms, it autogenerates phrases to help you expand your ideas.
Soovle includes unlimited searches for free. On the downside, it is limited to an idea generator and does not include metrics like keyword difficulty or search volume.
Keyword Tool Dominator helps you identify search trends as they happen. It brings you the autocomplete databases from Google, YouTube, Amazon, Walmart, Bing, Etsy, and eBay to uncover up-to-date keywords and search terms.
It’s an outstanding resource for sellers and multichannel marketers who want to rank on more than Google or the other search engines.
The downside of this fast and easy-to-use tool is the free version limits you to 2 searches a day. For more queries, you’ll need to pay for a plan.
![](http://sektorel.online/777/templates/cheerup/res/banner1.gif)
Keyword usage over time
Sometimes you want to know if a topic is an established trend or just a fad. In that case, Google Trends is a powerful and unique tool.
Google Trends is a free tool that delivers graphs and data on specific search terms used on Google and YouTube.
When you enter a search phrase on the homepage, it will deliver a list from Google by default. On the results page, you can change your options to see results from YouTube instead. It also offers trends from Google Shopping, Images, and News.
Google Trends is a valuable tool for:
- Identifying what’s currently trending
- Isolating popular topics or subtopics within an industry or related to a theme
- Discovering local search trends
- Finding related keywords that are growing in popularity
- Graphing the public interest in a topic over a range of time
- Seeing where a topic is most popular
Google Trends helps you identify keywords that are rising in popularity and avoid terms that are losing momentum. It does not provide data on monthly search volume or how much competition there is for each keyword phrase.
Free keyword research tools aren’t your only option. If your business is booming or you want to go down a new avenue, you can always invest in paid tools. Tools that require payment or a subscription to access do everything that the free tools above can do, but may also:
- Provide more keyword data
- Enable you to do more keyword research
- Feature location-based SEO tools
- Have rank trackers so you can see how well your website is ranking on SERP pages for certain keywords
- Have more user-friendly interfaces
- Have an all-in-one suite where you can conduct all your keyword research
If you are looking to branch into pay-per-click marketing, these tools may also offer additional insights into search engine marketing. (One free tool for paid marketing is Google Keyword Planner , which supplies data around Google’s biddable keywords.)
![google keyword research free](https://eep.io/images/yzco4xsimv0y/47q11VT7Ng0iqTb4iYyjcb/a1fb932dbca34a0a913f6870857fc600/Mailchimp_Content_Refresh_-35_Graphic_3.png?w=980&q=70)
Planning with data
Whether you are promoting a blog or building an e-commerce website, each page you create takes time, energy, and expertise. When you use the best keyword research tools for your business, you ensure your efforts produce results.
Don’t throw darts in the dark and hope they find their target. All the data you need to make solid content planning decisions is available in these 12 free keyword research tools.
Your audience knows what they want and need. Do you?
Best Keyword Research Tools: FAQ
Which tool is the best for keyword research.
When conducting SEO research , finding the best tool for keyword research can feel overwhelming, especially with the vast selection of both free and paid solutions available today. One of the most notable keyword research tools used today to help with understanding the top-performing keywords in any industry includes Keyword Surfer. Keyword Surfer is a well-known keyword research tool that can be used entirely for free from Surfer SEO.
Is Google keyword research tool free?
Yes. Both Google Trends and Google Keyword Planner are free keyword research tools that can be accessed by both individuals and business owners alike. With Google Trends and Google Keyword Planner, take advantage of free keyword tools that deliver top-tier results based on the latest algorithms in place by numerous search engines, including Google itself.
Using Google keyword research tools is highly recommended, especially if you are interested in boosting the ranking of your website or eCommerce store within Google search results themselves. With Google Trends, you can quickly and efficiently search for and compare keywords, phrases, and trends that are most relevant to your business and brand. Compare regions where your keywords are most popular as well as data as it has been collected and tracked over time. Using Google Trends is optimal for anyone who is seeking the best free keyword research tool or for those who are just getting started with keyword research for the first time.
Google Keyword Planner also provides a free keyword research tool that can help you plan for PPC and SEO marketing campaigns based on keyword popularity, usage, and market trends.
Are paid keyword research tools worth it?
At times, paid keyword research tools may be worth the investment, depending on the features you require as well as the budget you have for your next marketing campaign. Some paid keyword research tools provide additional keyword data, offer more results, and even include location-based SEO tools, which are optimal for those interested in locale-based targeting.
With paid keyword research tools, it is also often much easier to save and store your keyword research in one central location. You can also take advantage of rank trackers to determine how well individual pages on your website are currently performing with the tweaks you have made using your preferred paid keyword research tool.
How to choose the best keyword tool for your needs?
Before choosing the best free keyword research tool for your business or brand, consider your needs and the reason you are conducting keyword research. Ask yourself the following questions before determining whether a free or paid keyword research tool is right for you:
- What purpose is my keyword research going to serve? What am I attempting to learn or gain by conducting keyword research?
- Am I trying to spread the word about my business or brand with proper keywords and targeting, or am I attempting to generate sales with my keywords?
- How can I reach my users with relevant language and keywords? What keyword is my target audience most likely to search for while browsing for the products, services, or content I provide?
- Who is my current competition and how can I use popular keywords to boost my own ranking among my competition online?
- What features matter when it comes to a keyword research tool?
Knowing what features are necessary to achieve your own marketing goals can help in the process of eliminating keyword research tools that simply do not serve your needs.
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![9 FREE Google Tools for Keyword Research: Uncover Trends, Volumes, and Intent without Spending a Single Penny 9 FREE Google Tools for Keyword Research: Uncover Trends, Volumes, and Intent without Spending a Single Penny](https://gozen.io/images/blog/free-google-tools-for-keyword-research/featuredImage.jpg)
9 FREE Google Tools for Keyword Research: Uncover Trends, Volumes, and Intent without Spending a Single Penny
Gowtham Raj | 5 Min Read
In the ever-evolving landscape of digital marketing and search engine optimization (SEO), staying ahead of the curve is paramount. While seasoned SEO professionals and digital marketers often rely on a familiar set of paid keyword research tools, there exists a treasure trove of FREE resources right at their fingertips—tools developed by the search giant that dominates the online realm.
These tools, offered by none other than Google, have the potential to reshape your approach to keyword research. The keyword research is basically nothing but understanding the user intent.
If you are a solopreneur or small and medium-sized business (SMB), you will find this article helpful. The tools covered here are either unfamiliar to you, or you might not be fully acquainted with how to leverage them to their maximum capabilities.
I guarantee that you can find semantic keywords, trending keywords, search volumes of keywords, user intent queries, and more without spending a single penny.
Google tools are a gold mine for keyword research if you know how to properly use it.
Why Google Tools for Keyword Research Matters?
Effective SEO revolves around optimizing content to align with user intent. Also, the content needs to be helpful and must provide real-value to the users. This is what Google’s Helpful content system states.
To cater user intent, it is essential to find the trend at the right time and understand user behavior.
How do you find trends at the right time and understand user behavior?
We all know that when seeking valuable insights into customer behavior and staying updated with current trends, there’s no better resource than the formidable data powerhouse—Google.
Google has a suite of dedicated tools for both keyword research and PPC campaigns under Think with Google website and Google Ads account.
In fact many of the paid Keyword tools rely on Google Ads API. The Google Ads account and its API is not only for ad campaigns research and management; but also for keyword research.
Hence, it is wise to understand the importance of Google suite of tools and make the most out of it. You can still go for paid tools, if you want a smoother user interface or more ease of use.
FREE Google Tools for Keyword Research
Google Trends for identifying trending consumer behavior
Google Keyword Planner for identifying LSI keywords and search volume of keywords
Alphabet Soup, aka Google auto suggest, to identify variations, synonyms, and related keywords
Google Bard AI for finding LSI keywords, potential new keywords, long-tail keywords, user intent and pain points
People Also Ask Section for finding the most searched questions about a topic.
Related Searches Section for finding additional user questions
Site Colon Method is for competitor analysis
Sitemap Exploration is for competitor analysis
Google Alerts is to stay informed about fresh content
- Google Trends
Google Trends stands as a widely recognized tool for digital marketers and non-marketing professionals alike. What’s less commonly known is that Google Trends is part of the comprehensive toolkit offered by Think with Google.
Think with Google is an initiative by Google that provides insights, trends, and statistics pertaining to digital marketing, consumer behavior, and technology.
Okay, let’s delve into Google Trends.
Google Trends is a FREE effective tool that shows real-time trending search queries. It allows you to explore the relative search volume of specific keywords, topics, and queries across regions and languages.
In other words, Google Trends allows you to see what people are searching for during a particular timeline and in a particular region.
How to Effectively Use Google Trends for Keyword Research
1. Entering Topic or Search term : You can either input a specific search term or a topic. In case you are not sure about the specific keyword/ search term, you can go ahead with a broader perspective by giving the topic as input.
2. Comprehending the Data Visuals : Once you have given the input, you will be presented with a graph showing the trend over the time period that you have selected.
3. Compare Topic or Search term : Click “ Compare ” to compare your search terms or topics as shown in the screenshot below.
![google keyword research free compare search terms](https://gozen.io/_astro/compare_search_term.b6e117ad_Z1MtcW5.webp)
4. Segmentation Analysis : Scroll down a bit to reach “ Compared breakdown by sub-region ”. This section allows you to do segmented keyword research.
![google keyword research free segmentated analysis for keyword research](https://gozen.io/_astro/segmentated_analysis_for_keyword_research.d5044d7c_Z1pf2hx.webp)
5. LSI Keywords : At the end of the page, you will see “ Related topics ” and “ Related queries ”. This is where you can find the Latent Semantic Indexing (LSI) keywords and long-tail keywords.
![google keyword research free LSI Keywords](https://gozen.io/_astro/LSI_keywords.8fb1374d_W6ozC.webp)
6. Understanding the Jargon : It is essential to know what 1-100 and breakout mean in Google Trends to further proceed with your keyword research.
On Google Trends, a score of 100 indicates the highest search interest for the selected term, considering both time and location.
Another less-known term is “breakout,” signifying a remarkable increase of over 5000% in searches for related topics or queries.
This is how you can find out what keywords are trending, LSI keywords, and long-tail keywords in Google Trends.
- Google Keyword Planner
Google Keyword Planner is also a familiar tool amongst PPC experts and SEO specialists. It is one of the most popular tools in the suite offered by the Google Ads platform.
Unlike before, anyone with a Gmail account can access Google Keyword Planner. While primarily designed for Google Ads, the Keyword Planner is versatile and can also serve the purpose of keyword research. Unfortunately, many SEO experts often overlook its various features.
Neglecting to adjust the location filter is a common oversight, leading to suboptimal results in keyword research outcomes.
There are two separate section or tools inside Google Keyword Planner: one is used to find search volume of particular keywords and their forecasts , and the other one is used to find new semantic keywords —Latent Semantic Indexing (LSI)—as well as long tail keywords.
![google keyword research free Two_tools](https://gozen.io/_astro/Two_Tools.9c426fe0_Z2skCT0.webp)
Apart from these, there are features, such as:
- Broadening your seed keyword search
- Trend identification
- Brand name removal from your keyword research
- Grouping similar keywords
Among all these features, trend identification is one of my favorite features through which I have conquered SERPs many times.
To get to know all of these features within 6 minutes, check out our article: Keyword Planner for SEO Strategy: Revealing Overlooked Features . The article provides a step-by-step guide along with relevant screenshots.
Alphabet Soup, aka Google Auto Suggest
Alphabet Soup—aka Google Auto Suggest or Google Autocomplete—is one of the best ways to find great keywords for FREE.
Google Alphabet Soup is leveraging Google’s autocomplete feature to generate a list of potential keywords to a specific topic or search query.
The autocomplete suggestions represent a collection of related searches, essentially reflecting the queries conducted by other users.
The Google Alphabet Soup is one of the easiest ways to gather potential keywords and long-tail queries from users worldwide.
How to Use Google Alphabet Soup?
1. Type a specific keyword or a common search query
![google keyword research free Alphabet Soup](https://gozen.io/_astro/Alphabet_Soup.c9ce0d91_29EjMz.webp)
2. Observe the autocomplete suggestions
3. Templates to try for Top of the Funnel (TOFU) Content Ideas:
- “Seed keyword” + space
- “Seed keyword” + without space>
- “Seed keyword” + (Alphabet a to z)
- How to + modifier + prepositions + “Seed keyword”
- How do + * + “Seed keyword”
![google keyword research free Alphabet Soup, aka Google Auto Suggest](https://gozen.io/_astro/301.fa06e781_Z1L7I0g.webp)
4. Templates to try for Middle of the Funnel (MOFU) Content Ideas:
- Best + “Seed keyword” + *
- Best + * + for + “Seed keyword”
![google keyword research free Alphabet Soup MOFU](https://gozen.io/_astro/Alphabet_Soup_MOFU.f927e014_Z2269py.webp)
- Best “Seed keyword” for + *
5. Templates to try for Bottom of the Funnel (BOFU) Content Ideas:
Creating content for the bottom of the funnel (BOFU) requires a different approach, and it’s essential to think from the customer’s point of view.
Hence, there is only a limited template you can use for this purpose.
a. Alternatives to + “Brand or Seed keyword”
![google keyword research free Alphabet Soup BOFU](https://gozen.io/_astro/Alphabet_Soup_BOFU.75f8e646_ZVgrxJ.webp)
Google Bard AI
In the midst of the AI era, it’s impossible not to catch the wave of innovation that is Google Bard AI.
Google Bard is an interactive chat-based generative AI tool that is powered by the large language model (LLM), PaLM 2.
Generative AI models are sophisticated AI models that generate text, images, video, audio from text descriptions known as prompts.
You can leverage Google Bard to gather:
- Semantic keywords (aka LSI keywords)
- New potential keywords
- Long-tail keywords
- User intents and pain points
How to Use Google Bard AI for Keyword Research
1. Head to Bard website and sign in with your Gmail account.
2. Enter the prompt to perform certain tasks: You can use the below prompts to interact with the Google Bard for effective keyword research.
3. Prompt to discover new keywords : Generate a list of relevant keywords for a [your niche or topic] website
![google keyword research free Google Bard for Keyword research](https://gozen.io/_astro/Google_Bard_for_Keyword_research.b1425720_2rGcKr.webp)
For more information on the Bard’s response to my query: https://g.co/bard/share/5ed90f2adccc
4. Prompt to discover semantic keywords : Generate variations of the keyword [your main keyword] to include different phrasings, synonyms, and semantic keywords.
5. Prompt to discover long-tail keywords : Discover long-tail keywords for [specific aspect or feature] in [your industry]
6. Prompt for competitor analysis : Provide insights into keywords targeted by [competitor’s name] in [industry/niche].
7. Prompt to understand user intent : Analyze user intent for searches related to [your main topic] and suggest keywords that align with that intent
8. Prompt to understand customer pain points : Identify common pain points experienced by customers in [your industry/niche]. Generate insights into the challenges and frustrations users face when [engaging with/buying/using] [your product/service].
Once you gather a list of keywords from Bard, ensure to insert it into Google Keyword Planner to gain insights , such as search volumes and more new semantic keywords.
People Also Ask (PAA) Section
People Also Ask (PAA), aka related questions group , is a collection of similar questions related to the search query of what the user typed in lately.
PAA is dynamically generated using the knowledge graph algorithm that identifies common questions related to the user’s search query, providing a more interactive and dynamic search experience.
This section usually appears just below the first result in Google SERP. Typically, the section comprises four questions. Upon examining the final question, Google will automatically present a new set of questions.
Exploring the People Also Ask section is the best way to find most searched questions about a topic.
How to Use People Also Ask Section Effectively?
All you have to do is type in your seed keyword or semantic keywords in the Google search box and gather as many People Also Ask questions as possible.
![google keyword research free People Also Ask Questions](https://gozen.io/_astro/People_Also_Ask_Questions.9bd0f403_11jBzF.webp)
After compiling all the questions, you can respond to them indirectly within a specific section of your article, or alternatively, address them directly by incorporating the exact questions into a dedicated Frequently Asked Questions (FAQ) section.
- Related Searches Section
The Related Searches Section of Google SERP is a list of additional queries that are related to the user’s original search term.
Clicking on one of the related searches will initiate a new search query, providing the user with a set of results tailored to the selected related search term.
It usually appears at the bottom of the SERP page. Since Google recently launched the Continuous scrolling feature, you can find this section after ten results.
Exploring Related Searches Section is a good way to expand your keyword list since it gives synonyms and variations of your seed keyword. You can also use it to analyze what terms your competitors are targeting.
How to Use Related Searches Section?
1. Enter your seed keyword or any semantic keywords
2. Scrolling down to reach the Related Searches Section
![google keyword research free Related Searches Section](https://gozen.io/_astro/Related_Searches_Section.acde970d_Z1HyKVG.webp)
That’s it. Simple.
- Site Colon Method
Site Colon is an advanced search operator that is used to find indexed pages of a specific website. It can be used to gain insights of your competitor website’s indexed content and the keywords associated with it.
This Site Colon is not a standalone keyword research tool. However, it can be a supplementary approach to gather insights into a website’s content and the keywords associated with it.
![google keyword research free Site colon method](https://gozen.io/_astro/Site_colon_method.addf26d7_YpTh0.webp)
How to Use Site Colon Method for Keyword Research?
1. Syntax: site:competitor.com. It displays all the indexed pages of the site “competitor”.com. You can type in the syntax manually or use an extension called “ Search the current site ”.
2. You can even fine-tune the results by adjusting the syntax as shown below:
1. Site:competitor.com/blog
3. Now, go through all the meta descriptions and titles to identify the competitor keywords.
Sitemap Exploration
Sitemap exploration is one of the most underestimated techniques, which can be used as an alternative to the Site Colon method discussed above.
Sitemap is a file that lists all the pages of a website and provides information about its organization and structure.
Every company or website on the web must have a proper sitemap as an ethical practice of SEO.
By exploring a sitemap of your competitor, you can identify:
- Topical authority and content volume
- Discover new keywords
- Recent update
- Priority pages
How to Use Sitemap Exploration for Keyword Research
1. Use the following syntax https://competitor.com/sitemap.xml to explore the sitemap of your competitors. In case you are caught up with page not found error, try adding sitemap-0.xml or sitemap-1.xml, or sitemap-index.xml
2. To find topical authority and content volume, explore the content hierarchy and categories section of the sitemap
3. Search “last modified” to identify the latest change they made, which can be a trending topic to cover on
4. Explore different section of the sitemap to find new keywords
- Google Alerts
Introduced by Google on August 6, 2003, Google Alerts is a longstanding service that detects changes in content and notifies users accordingly.
Unlike Google Trends, which analyzes real-time trends, Google Alerts focuses on providing notifications about new content related to specified keywords in Google’s search results. This notification service keeps users informed whenever there is fresh content matching their defined criteria.
How to Use Google Alerts for Keyword Research?
- Go to Google Alerts website and enter the keyword that you want to monitor
- Select your Gmail account to receive notifications
- Lastly, click “Show options” to optimize the frequency, sources, region, and language of the notification.
![google keyword research free Google Alerts](https://gozen.io/_astro/Google_Alerts.f4b01ce8_1sA9TD.webp)
1. How do I find SEO keywords for FREE?
Anyone can find potential SEO keywords for their niches, without even spending a single penny.
Yes, there are numerous Google tools and features available for everyone to utilize in conducting comprehensive keyword research:
- Google Bard
- Alphabet Soup, aka Google auto suggest, to identify
- People Also Ask Section
2. Is there a fee to use Google’s keyword research tool?
Anyone can use Google’s keyword research tool free of cost. All you need is a Gmail account to access the suite of Google tools.
You can even access a few Google tools/ features without a Gmail account.
3. What is the difference between People Also Ask (PAA) and Related Searches Section?
While both the PAA and Related Searches sections aim to assist users in finding relevant information, they do so in slightly different ways.
PAA offers a dynamic set of questions related to the user’s query , while the Related Searches section provides additional search term suggestions for users looking to explore related topics .
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Use Keyword Planner
Tip : If you’re affected by market changes , we recommend planning weekly rather than monthly or quarterly until markets stabilise.
Keyword Planner’s forecasts are refreshed daily and based on the last 7–10 days, adjusted for seasonality. Your forecasts will take into account any impact of market changes during this time frame. We’ve updated our seasonal model to account for current market conditions.
Keyword Planner helps you research keywords for your search campaigns .
You can use this free tool to discover new keywords related to your business and see estimates of the searches that they receive and the cost to target them.
Keyword Planner also provides another way to create search campaigns that’s centred around in-depth keyword research.
This article shows you how to use Keyword Planner to lay the groundwork for a successful campaign.
- Discover new keywords: Get suggestions for keywords related to your products, services or website.
- See monthly searches: See estimates on the number of searches that a keyword gets each month.
- Determine cost: See the average cost for your ad to show on searches for a keyword.
- Organise keywords: See how your keywords fit into different categories related to your brand.
- Create new campaigns: Use your keyword plan to create new campaigns centred on in-depth keyword research.
Bear in mind that while Keyword Planner can provide insights into keyword targeting, campaign performance depends on a variety of factors. For example, your bid, budget, product and customer behaviour in your industry can all influence the success of your campaigns.
Instructions
To access Keyword Planner:
- Your account must be using Expert mode . You won’t be able to access Keyword Planner if your account is using Smart mode .
- You must complete your account setup by entering your billing information and creating a campaign. If you’re not yet ready to spend money, you can choose to pause your campaigns .
1. Create a keyword plan
Once you open Keyword Planner , there are two ways to create your keyword plan:
- Search for new keywords by clicking Discover new keywords .
- Upload existing keywords by clicking Get search volume and forecasts .
Discover new keywords
Enter words and/or websites related to your business to see keyword ideas. Learn more About Google Ads manager accounts
- Click the Planning drop-down in the section menu.
- Click Keyword planner .
- Click Discover new keywords.
- Enter your domain and Google will try to exclude keywords not related to what you offer.
- Start with a website: Enter any website and Google will look for keywords related to the content on that site. Note: the contents of hyperlinks aren’t used to generate keyword ideas.
- Click Get results.
After clicking 'Get results', you’ll see a list of keywords related to what you entered. These keywords haven’t been added to your plan. You can now edit your list with filters and categories to help you find those that make sense for your plan.
B. Edit your list of keyword ideas
You can now edit your list of keyword ideas using filters and categories. Learn more in-depth tips on editing your keyword list .
Narrow down your list of keywords based on criteria like competition, impression share and keyword text. For example, you may want to see keyword ideas where bids under £1 may be enough to reach the top of the page.
- Click Add filter .
- Select a filter and enter its values.
- Your list of ideas will now match the filter.
Refine by category
See groups of keywords based on their themes, brands or categories.
- Look for the 'Refine keywords' side panel on the 'Keyword ideas' page.
- Open the categories beneath it to see characteristics related to your keyword ideas.
- For example, if your keywords are related to running shoes, you may see a category for shoe color. To only see keywords for 'red running shoes,' you’d uncheck the box for all other colours.
C. Add keywords to your plan and see a performance forecast
- Add them to your 'Saved keywords' to organise them later and see forecasts of their performance.
- Add them to ad groups within existing campaigns.
Follow these steps to add keywords to your plan and forecast their performance:
- Tick the box next to each keyword that you’d like to add to your plan. Adding keywords to 'Saved keywords' enables you to save them to your plan and organise them later.
- Specify the match type by clicking the Broad match drop-down and selecting a match type.
- Click Add keywords to create a new plan or click Add keywords to add the keywords to an existing plan.
Get search volume and forecasts
- Click Get search volume and forecasts .
- Click Upload a file .
- Upload a list of keywords: Your file should have just one column with the header titled 'Keyword'.
- Upload an entire keyword plan: Download the template to include optional data like campaign, location and ad group. along with your keyword.
- Click Submit .
- Click Get started .
2. Understand your keyword forecast
Your plan forecast shows you how many conversions, clicks or impressions you’re likely to get for your keywords based on your spend. Learn more about Keyword Planner forecasts
Understand your forecast
Your forecast is available on the 'Forecasts' page of your plan. It includes keywords that you uploaded through 'Get search volumes and forecasts' or those that you added from the 'Keyword ideas' page.
What’s included in your forecast
- Change the metric that you’re forecasting by clicking 'Conversions' or 'Clicks'. This is available to you when you enable conversion tracking in your account. Otherwise, click 'Add conversion metrics' to review the options.
- Change the average daily budget by clicking the amount.
- Change your bid strategy by clicking the 'Maximise clicks' drop-down.
- Click the drop-down arrow to see a chart of your estimated performance to get based on your spend.
- Edit the amount in the 'Average daily budget' to see how these estimates change.
- Ad groups that your keywords will be added to in a new campaign if you implement your plan.
- Click on the date range at the top of the page to change the timeframe for your forecast.
Additional options
- Add new keywords by clicking the plus button and entering new keywords. You can also return to the 'Keyword ideas' page and add keywords from there.
- Download forecast by clicking the download button.
- Share plan with others by clicking the Share button and enabling share access.
3. Organise keywords into ad groups (English only)
Organise keywords.
Enter words or websites related to your business to see keyword ideas.
- Click Organise keywords into ad groups .
- Start with a website: Enter any website and Google will look for keywords related to the content on that site.
- Upload or paste: Upload a file or enter keywords. Keyword Planner will try to organise keywords into your campaigns, or you can manually organise them yourself.
- Click Auto-organise keywords .
After clicking 'Auto-organise keywords', you’ll see a list of ad groups with keyword suggestions. We’ll try to match them with the most relevant ad groups in your highest performing campaigns. Once complete, you’ll be able to review them for accuracy and make edits of your own. You can also download your work for review. No changes will be made to your account until you’re ready to upload them.
Send us feedback
Related links
- Refine your new keywords in Keyword Planner
- About Keyword Planner forecasts
- Best practices for finding new keywords
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A review of computer vision-based crack detection methods in civil infrastructure: progress and challenges.
![ORCID google keyword research free](https://pub.mdpi-res.com/img/design/orcid.png?0465bc3812adeb52?1723031622)
1. Introduction
2. crack detection combining traditional image processing methods and deep learning, 2.1. crack detection based on image edge detection and deep learning, 2.2. crack detection based on threshold segmentation and deep learning, 2.3. crack detection based on morphological operations and deep learning, 3. crack detection based on multimodal data fusion, 3.1. multi-sensor fusion, 3.2. multi-source data fusion, 4. crack detection based on image semantic understanding, 4.1. crack detection based on classification networks, 4.2. crack detection based on object detection networks, 4.3. crack detection based on segmentation networks.
Model | Improvement/Innovation | Backbone/Feature Extraction Architecture | Efficiency | Results |
---|---|---|---|---|
FCS-Net [ ] | Integrating ResNet-50, ASPP, and BN | ResNet-50 | - | MIoU = 74.08% |
FCN-SFW [ ] | Combining fully convolutional network (FCN) and structural forests with wavelet transform (SFW) for detecting tiny cracks | FCN | Computing time = 1.5826 s | Precision = 64.1% Recall = 87.22% F1 score = 68.28% |
AFFNet [ ] | Using ResNet101 as the backbone network, and incorporating two attention mechanism modules, namely VH-CAM and ECAUM | ResNet101 | Execution time = 52 ms | MIoU = 84.49% FWIoU = 97.07% PA = 98.36% MPA = 92.01% |
DeepLabv3+ [ ] | Replacing ordinary convolution with separable convolution; improved SE_ASSP module | Xception-65 | - | AP = 97.63% MAP = 95.58% MIoU = 81.87% |
U-Net [ ] | The parameters were optimized (the depths of the network, the choice of activation functions, the selection of loss functions, and the data augmentation) | Encoder and decoder | Analysis speed (1024 × 1024 pixels) = 0.022 s | Precision = 84.6% Recall = 72.5% F1 score = 78.1% IoU = 64% |
KTCAM-Net [ ] | Combined CAM and RCM; integrating classification network and segmentation network | DeepLabv3 | FPS = 28 | Accuracy = 97.26% Precision = 68.9% Recall = 83.7% F1 score = 75.4% MIoU = 74.3% |
ADDU-Net [ ] | Featuring asymmetric dual decoders and dual attention mechanisms | Encoder and decoder | FPS = 35 | Precision = 68.9% Recall = 83.7% F1 score = 75.4% MIoU = 74.3% |
CGTr-Net [ ] | Optimized CG-Trans, TCFF, and hybrid loss functions | CG-Trans | - | Precision = 88.8% Recall = 88.3% F1 score = 88.6% MIoU = 89.4% |
PCSN [ ] | Using Adadelta as the optimizer and categorical cross-entropy as the loss function for the network | SegNet | Inference time = 0.12 s | mAP = 83% Accuracy = 90% Recall = 50% |
DEHF-Net [ ] | Introducing dual-branch encoder unit, feature fusion scheme, edge refinement module, and multi-scale feature fusion module | Dual-branch encoder unit | - | Precision = 86.3% Recall = 92.4% Dice score = 78.7% mIoU = 81.6% |
Student model + teacher model [ ] | Proposed a semi-supervised semantic segmentation network | EfficientUNet | - | Precision = 84.98% Recall = 84.38% F1 score = 83.15% |
5. Datasets
6. evaluation index, 7. discussion, 8. conclusions, author contributions, data availability statement, acknowledgments, conflicts of interest.
Aspect | Combining Traditional Image Processing Methods and Deep Learning | Multimodal Data Fusion |
---|---|---|
Processing speed | Moderate—traditional methods are usually fast, but deep learning models may be slower, and the overall speed depends on the complexity of the deep learning model | Slower—data fusion and processing speed can be slow, especially with large-scale multimodal data, involving significant computational and data transfer overhead |
Accuracy | High—combines the interpretability of traditional methods with the complex pattern handling of deep learning, generally resulting in high detection accuracy | Typically higher—combining different data sources (e.g., images, text, audio) provides comprehensive information, improving overall detection accuracy |
Robustness | Strong—traditional methods provide background knowledge, enhancing robustness, but deep learning’s risk of overfitting may reduce robustness | Very strong—fusion of multiple data sources enhances the model’s adaptability to different environments and conditions, better handling noise and anomalies |
Complexity | High—integrating traditional methods and deep learning involves complex design and balancing, with challenges in tuning and interpreting deep learning models | High—involves complex data preprocessing, alignment, and fusion, handling inconsistencies and complexities from multiple data sources |
Adaptability | Strong—can adapt to different types of cracks and background variations, with deep learning models learning features from data, though it requires substantial labeled data | Very strong—combines diverse data sources, adapting well to various environments and conditions, and handling complex backgrounds and variations effectively |
Interpretability | Higher—traditional methods provide clear explanations, while deep learning models often lack interpretability; combining them can improve overall interpretability | Lower—fusion models generally have lower interpretability, making it difficult to intuitively explain how different data sources influence the final results |
Data requirements | High—deep learning models require a lot of labeled data, while traditional methods are more lenient, though deep learning still demands substantial data | Very high—requires large amounts of data from various modalities, and these data need to be processed and aligned effectively for successful fusion |
Flexibility | Moderate—combining traditional methods and deep learning handles various types of cracks, but may be limited in very complex scenarios | High—handles multiple data sources and different crack information, improving performance in diverse conditions through multimodal fusion |
Real-time capability | Poor—deep learning models are often slow to train and infer, making them less suitable for real-time detection, though combining with traditional methods can help | Poor—multimodal data fusion processing is generally slow, making it less suitable for real-time applications |
Maintenance cost | Moderate to high—deep learning models require regular updates and maintenance, while traditional methods have lower maintenance costs | High—involves ongoing maintenance and updates for multiple data sources, with complex data preprocessing and fusion processes |
Noise handling | Good—traditional methods effectively handle noise under certain conditions, and deep learning models can mitigate noise effects through training | Strong—multimodal fusion can complement information from different sources, improving robustness to noise and enhancing detection accuracy |
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Click here to enlarge figure
Method | Features | Domain | Dataset | Image Device/Source | Results | Limitations |
---|---|---|---|---|---|---|
Canny and YOLOv4 [ ] | Crack detection and measurement | Bridges | 1463 images 256 × 256 pixels | Smartphone and DJI UAV | Accuracy = 92% mAP = 92% | The Canny edge detector is affected by the threshold |
Canny and GM-ResNet [ ] | Crack detection, measurement, and classification | Road | 522 images 224 × 224 pixels | Concrete crack sub-dataset | Precision = 97.9% Recall = 98.9% F1 measure = 98.0% Accuracy in shadow conditions = 99.3% Accuracy in shadow-free conditions = 99.9% | Its detection performance for complex cracks is not yet perfect |
Sobel and ResNet50 [ ] | Crack detection | Concrete | 4500 images 100 × 100 pixels | FLIR E8 | Precision = 98.4% Recall = 88.7% F1 measure = 93.2% | - |
Sobel and BARNet [ ] | Crack detection and localization | Road | 206 images 800 × 600 pixels | CrackTree200 dataset | AIU = 19.85% ODS = 79.9% OIS = 81.4% | Hyperparameter tuning is needed to balance the penalty weights for different types of cracks |
Canny and DeepLabV3+ [ ] | Crack detection | Road | 2000 × 1500 pixels | Crack500 dataset | MIoU = 77.64% MAE = 1.55 PA = 97.38% F1 score = 63% | Detection performance deteriorating in dark environments or when interfering objects are present |
Canny and RetinaNet [ ] | Crack detection and measurement | Road | 850 images 256 × 256 pixels | SDNET 2018 dataset | Precision = 85.96% Recall = 84.48% F1 score = 85.21% | - |
Canny and Transformer [ ] | Crack detection and segmentation | Buildings | 11298 images 450 × 450 pixels | UAVs | GA = 83.5% MIoU = 76.2% Precision = 74.3% Recall = 75.2% F1 score = 74.7% | Resulting in a marginal increment in computational costs for various network backbones |
Canny and Inception-ResNet-v2 [ ] | Crack detection, measurement, and classification | High-speed railway | 4650 images 400 × 400 pixels | The track inspection vehicle | High severity level: Precision = 98.37% Recall = 93.82% F1 score = 95.99% Low severity level: Precision = 94.25% Recall = 98.39% F1 score = 96.23% | Only the average width was used to define the severity of the crack, and the influence of the length on the detection result was not considered |
Canny and Unet [ ] | Crack detection | Buildings | 165 images | - | SSIM = 14.5392 PSNR = 0.3206 RMSE = 0.0747 | Relies on a large amount of mural data for training and enhancement |
Method | Features | Domain | Dataset | Image Device/Source | Results | Limitations |
---|---|---|---|---|---|---|
Otsu and Keras classifier [ ] | Crack detection, measurement, and classification | Concrete | 4000 images 227 × 227 pixels | Open dataset available | Classifiers accuracy = 98.25%, 97.18%, 96.17% Length error = 1.5% Width error = 5% Angle of orientation error = 2% | Only accurately quantify one single crack per image |
Otsu and TL MobileNetV2 [ ] | Crack detection, measurement, and classification | Concrete | 11435 images 224 × 224 pixels | Mendeley data—crack detection | Accuracy = 99.87% Recall = 99.74% Precision = 100% F1 score = 99.87% | Dependency on image quality |
Otsu, YOLOv7, Poisson noise, and bilateral filtering [ ] | Crack detection and classification | Bridges | 500 images 640 × 640 pixels | Dataset | Training time = 35 min Inference time = 8.9 s Target correct rate = 85.97% Negative sample misclassification rate = 42.86% | It does not provide quantified information such as length and area |
Adaptive threshold and WSIS [ ] | Crack detection | Road | 320 images 3024 × 4032 pixels | Photos of cracks | Recall = 90% Precision = 52% IoU = 50% F1 score = 66% Accuracy = 98% | For some small cracks (with a width of less than 3 pixels), model can only identify the existence of small cracks, but it is difficult to depict the cracks in detail |
Adaptive threshold and U-GAT-IT [ ] | Crack detection | Road | 300 training images and237 test images | DeepCrack dataset | Recall = 79.3% Precision = 82.2% F1 score = 80.7% | Further research is needed to address the interference caused by factors such as small cracks, road shadows, and water stains |
Local thresholding and DCNN [ ] | Crack detection | Concrete | 125 images 227 × 227 pixels | Cameras | Accuracy = 93% Recall = 91% Precision = 92% F1 score = 91% | - |
Otsu and Faster R-CNN [ ] | Crack detection, localization, and quantification | Concrete | 100 images 1920 × 1080 pixels | Nikon d7200 camera and Galaxy s9 camera | AP = 95% mIoU = 83% RMSE = 2.6 pixels Length accuracy = 93% | The proposed method is useful for concrete cracks only; its applicability for the detection of other crack materials might be limited |
Adaptive Dynamic Thresholding Module (ADTM) and Mask DINO [ ] | Crack detection and segmentation | Road | 395 images 2000 × 1500 pixels | Crack500 | mIoU = 81.3% mAcc = 96.4% gAcc = 85.0% | ADTM module can only handle binary classification problems |
Dynamic Thresholding Branch and DeepCrack [ ] | Crack detection and classification | Bridges | 3648 × 5472 pixels | Crack500 | mIoU = 79.3% mAcc = 98.5% gAcc = 86.6% | Image-level thresholds lead to misclassification of the background |
Method | Features | Domain | Dataset | Image Device/Source | Results | Limitations |
---|---|---|---|---|---|---|
Morphological closing operations and Mask R-CNN [ ] | Crack detection | Tunnel | 761 images 227 × 227 pixels | MTI-200a | Balanced accuracy = 81.94% F1 score = 68.68% IoU = 52.72% | Relatively small compared to the needs of the required sample size for universal conditions |
Morphological operations and Parallel ResNet [ ] | Crack detection and measurement | Road | 206 images (CrackTree200) 800 × 600 pixels and 118 images (CFD) 320 × 480 pixels | CrackTree200 dataset and CFD dataset | CrackTree200: Precision = 94.27% Recall = 92.52% F1 = 93.08% CFD: Precision = 96.21% Recall = 95.12% F1 = 95.63% | The method was only performed on accurate static images |
Closing and CNN [ ] | Crack detection, measurement, and classification | Concrete | 3208 images 256 × 256 pixels or 128 × 128 pixels | Hand-held DSLR cameras | Relative error = 5% Accuracy > 95% Loss < 0.1 | The extraction of the cracks’ edge will have a larger influence on the results |
Dilation and TunnelURes [ ] | Crack detection, measurement, and classification | Tunnel | 6810 images image sizes vary 10441 × 2910 to 50739 × 3140 | Night 4K line-scan cameras | AUC = 0.97 PA = 0.928 IoU = 0.847 | The medial-axis skeletonization algorithm created many errors because it was susceptible to the crack intersection and the image edges where the crack’s representation changed |
Opening, closing, and U-Net [ ] | Crack detection, measurement, and classification | Concrete | 200 images 512 × 512 pixels | Canon SX510 HS camera | Precision = 96.52% Recall = 93.73% F measure = 96.12% Accuracy = 99.74% IoU = 78.12% | It can only detect the other type of cracks which have the same crack geometry as that of thermal cracks |
Morphological operations and DeepLabV3+ [ ] | Crack detection and measurement | Masonry structure | 200 images 780 × 355 pixels and 2880 × 1920 pixels | Internet, drones, and smartphones | IoU = 0.97 F1 score = 98% Accuracy = 98% | The model will not detect crack features that do not appear in the dataset (complicated cracks, tiny cracks, etc.) |
Erosion, texture analysis techniques, and InceptionV3 [ ] | Crack detection and classification | Bridges | 1706 images 256 × 256 pixels | Cameras | F1 score = 93.7% Accuracy = 94.07% | - |
U-Net, opening, and closing operations [ ] | Crack detection and segmentation | Bridges | 244 images 512 × 512 pixels | Cameras | mP = 44.57% mR = 53.13% Mf1 = 42.79% mIoU = 64.79% | The model lacks generality, and there are cases of false detection |
Sensor Type | Fusion Method | Advantages | Disadvantages | Application Scenarios |
---|---|---|---|---|
Optical sensor [ ] | Data-level fusion | High resolution, rich in details | Susceptible to light and occlusion | Surface crack detection, general environments |
Thermal sensor [ ] | Feature level fusion | Suitable for nighttime or low-light environments, detects temperature changes | Low resolution, lack of detail | Nighttime detection, heat-sensitive areas, large-area surface crack detection |
Laser sensor [ ] | Data-level fusion and feature level fusion | High-precision 3D point cloud data, accurately measures crack morphology | High equipment cost, complex data processing | Complex structures, precise measurements |
Strain sensor [ ] | Feature level fusion and decision-level fusion | High sensitivity to structural changes; durable | Requires contact with the material; installation complexity | Monitoring structural health in bridges and buildings; detecting early-stage crack development |
Ultrasonic sensor [ ] | Data-level fusion and feature level fusion | Detects internal cracks in materials, strong penetration | Affected by material and geometric shape, limited resolution | Internal cracks, metal material detection |
Optical fiber sensor [ ] | Feature level fusion | High sensitivity to changes in material properties, non-contact measurement | Affected by environmental conditions, requires calibration | Surface crack detection, structural health monitoring |
Vibration sensor [ ] | Data-level fusion | Detects structural vibration characteristics, strong adaptability | Affected by environmental vibrations, requires complex signal processing | Dynamic crack monitoring, bridges and other structures |
Multispectral satellite sensor [ ] | Data-level fusion | Rich spectral information | Limited spectral resolution, weather- and lighting-dependent, high cost | Pavement crack detection, bridge and infrastructure monitoring, building facade inspection |
High-resolution satellite sensors [ ] | Data-level fusion and feature level fusion | High spatial resolution, wide coverage, frequent revisit times, rich information content | Weather dependency, high cost, data processing complexity, limited temporal resolution | Road and pavement crack detection, bridge and infrastructure monitoring, urban building facade inspection, railway and highway crack monitoring |
Scale | Dataset/(Pixels × Pixels) | References |
---|---|---|
Image-based | 227 × 227 | [ , , , ] |
224 × 224 | [ ] | |
256 × 256 | [ ] | |
416 × 416 | [ ] | |
512 × 512 | [ ] | |
Patch-based | 128 × 128 | [ , ] |
200 × 200 | [ ] | |
224 × 224 | [ , , , , ] | |
227 × 227 | [ ] | |
256 × 256 | [ , ] | |
300 × 300 | [ , ] | |
320 × 480 | [ , ] | |
544 × 384 | [ ] | |
512 × 512 | [ , , , ] | |
584 × 384 | [ ] |
Model | Improvement/Innovation | Dataset | Backbone | Results |
---|---|---|---|---|
Faster R-CNN [ ] | Combined with drones for crack detection | 2000 images 5280 × 2970 pixels | VGG-16 | Precision = 92.03% Recall = 96.26% F1 score = 94.10% |
Faster R-CNN [ ] | Double-head structure is introduced, including an independent fully connected head and a convolution head | 1622 images 1612 × 1947 pixels | ResNet50 | AP = 47.2% |
Mask R-CNN [ ] | The morphological closing operation was incorporated into the M-R-101-FPN model to form an integrated model | 761 images 227 × 227 pixels | ResNets and VGG | Balanced accuracy = 81.94% F1 score = 68.68% IoU = 52.72% |
Mask R-CNN [ ] | PAFPN module and edge detection branch was introduced | 9680 images 1500 × 1500 pixels | ResNet-FPN | Precision = 92.03% Recall = 96.26% AP = 94.10% mAP = 90.57% Error rate = 0.57% |
Mask R-CNN [ ] | FPN structure introduces side join method and combines FPN with ResNet-101 to change RoI-Pooling layer to RoI-Align layer | 3430 images 1024 × 1024 pixels | ResNet101 | AP = 83.3% F1 score = 82.4% Average error = 2.33% mIoU = 70.1% |
YOLOv3-tiny [ ] | A structural crack detection and quantification method combined with structured light is proposed | 500 images 640 × 640 pixels | Darknet-53 | Accuracy = 94% Precision = 98% |
YOLOv4 [ ] | Some lightweight networks were used instead of the original backbone feature extraction network, and DenseNet, MobileNet, and GhostNet were selected for the lightweight networks | 800 images 416 × 416 pixels | DenseNet, MobileNet v1, MobileNet v2, MobileNet v3, and GhostNet | Precision = 93.96% Recall = 90.12% F1 score = 92% |
YOLOv4 [ ] | - | 1463 images 256 × 256 pixels | Darknet-53 | Accuracy = 92% mAP = 92% |
Datasets Name | Number of Images | Image Resolution | Manual Annotation | Scope of Applicability | Limitations |
---|---|---|---|---|---|
CrackTree200 [ ] | 206 images | 800 × 600 pixels | Pixel-level annotations for cracks | Crack classification and segmentation | With only 200 images, the dataset’s relatively small size can hinder the model’s ability to generalize across diverse conditions, potentially leading to overfitting on the specific examples provided |
Crack500 [ ] | 500 images | 2000 × 1500 pixels | Pixel-level annotations for cracks | Crack classification and segmentation | Limited number of images compared to larger datasets, which might affect the generalization of models trained on this dataset |
SDNET 2018 [ ] | 56000 images | 256 × 256 pixels | Pixel-level annotations for cracks | Crack classification and segmentation | The dataset’s focus on concrete surfaces may limit the model’s performance when applied to different types of surfaces or structures |
Mendeley data—crack detection [ ] | 40000 images | 227 × 227 pixels | Pixel-level annotations for cracks | Crack classification | The dataset might not cover all types of cracks or surface conditions, which can limit its applicability to a wide range of real-world scenarios |
DeepCrack [ ] | 2500 images | 512 × 512 pixels | Annotations for cracks | Crack segmentation | The resolution might limit the ability of models to capture very small or subtle crack features |
CFD [ ] | 118 images | 320 × 480 pixels | Pixel-level annotations for cracks | Crack segmentation | The dataset contains a limited number of data samples, which may limit the generalization ability of the model |
CrackTree260 [ ] | 260 images | 800 × 600 pixels and 960 × 720 pixels | Pixel-level labeling, bounding boxes, or other crack markers | Object detection and segmentation | Because the dataset is small, it can be easy for the model to overfit the training data, especially if you’re using a complex model |
CrackLS315 [ ] | 315 images | 512 × 512 pixels | Pixel-level segmentation mask or bounding box | Object detection and segmentation | The small size of the dataset may make the model perform poorly in complex scenarios, especially when encountering different types of cracks or uncommon crack features |
Stone331 [ ] | 331 images | 512 × 512 pixels | Pixel-level segmentation mask or bounding box | Object detection and segmentation | The relatively small number of images limits the generalization ability of the model, especially in deep learning tasks where smaller datasets tend to lead to overfitting |
Index | Index Value and Calculation Formula | Curve |
---|---|---|
True positive | - | |
False positive | - | |
True negative | - | |
False negative | - | |
Precision | PRC | |
Recall | PRC, ROC curve | |
F1 score | F1 score curve | |
Accuracy | Accuracy vs. threshold curve | |
Average precision | PRC | |
Mean average precision | - | |
IoU | IoU distribution curve, precision-recall curve with IoU thresholds |
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Share and Cite
Yuan, Q.; Shi, Y.; Li, M. A Review of Computer Vision-Based Crack Detection Methods in Civil Infrastructure: Progress and Challenges. Remote Sens. 2024 , 16 , 2910. https://doi.org/10.3390/rs16162910
Yuan Q, Shi Y, Li M. A Review of Computer Vision-Based Crack Detection Methods in Civil Infrastructure: Progress and Challenges. Remote Sensing . 2024; 16(16):2910. https://doi.org/10.3390/rs16162910
Yuan, Qi, Yufeng Shi, and Mingyue Li. 2024. "A Review of Computer Vision-Based Crack Detection Methods in Civil Infrastructure: Progress and Challenges" Remote Sensing 16, no. 16: 2910. https://doi.org/10.3390/rs16162910
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