All friends doing SEO content have encountered this dilemma: you finally find a free and useful keyword tool, and just as you get used to it, it starts charging a fee or limits the number of queries. We spent a lot of time testing and found 7 free keyword research tools that are truly unlimited, and more importantly, we verified their accuracy with real Google Search Console data. The results might surprise you.
Keyword research is more than just checking search volume. If no one searches for a term, what's the point of spending time writing content about it? If your new site wants to compete for popular keywords against government websites or industry authority sites, the chance of success is almost zero. For new sites, the core of keyword research is to find terms that have: a monthly search volume of at least 100, and low to medium competition.
What is most appealing about Ryan Robinson's free keyword tool (access at: ryrob.com/keyword-tool/) is the founder's promise of permanent free and unlimited use. Taking "best WooCommerce plugins" as an example, the tool displays search volume and keyword difficulty ratings. However, it's important to note that the difficulty rating is only a reference, especially for new sites, where more in-depth competitive analysis is crucial.
My approach is: search the term directly on Google and use the Ubersuggest browser extension to check the Domain Authority (DA) of the ranking pages. If the DA of all the top 10 results exceeds 40, this keyword is too difficult for a new site. For terms occupied by large sites like Hostinger and WPBeginner, new sites are best advised to steer clear.
New sites should look for keywords where the top 10 results include a mix of low-authority sites (DA < 40) and high-authority sites, with a monthly search volume of 100+. However, if your site has already published 300+ articles, the strategy changes – you should then focus on building topical authority. As long as the search volume is reasonable, you can afford to relax the competition level.
The tool also recommends related keywords, such as extending from "WooCommerce plugins" to "WooCommerce subscription plugins," "booking plugins," and other directions you might not have considered. This is very valuable for content planning.
HOTH's tool is backed by Semrush's database, an otherwise expensive paid tool. The free version provides data such as CPC (Cost Per Click) and competition scores. It's important to note that the "competition" here is more geared towards advertising placement and doesn't fully apply to organic search ranking judgment.
The tool displays a difficulty score, with anything over 40 considered high competition. However, I still recommend going back to Google and verifying with an actual search. Its advantage lies in providing more keyword suggestions, which can be used in conjunction with other tools to expand your ideas.
Particularly worth mentioning is the search intent tagging. For example, "Rank Math tutorial" is marked as informational intent, indicating that users want to learn how to use this tool. Understanding search intent is a prerequisite for content creation; otherwise, even if you rank, the bounce rate will be high.
Although Ahrefs is a giant in the paid tool space, their free Keyword Generator supports data queries for Google, Bing, YouTube, and Amazon. This is particularly useful for those doing video SEO or e-commerce.
The way the tool presents information is a bit different. It displays "Alphabet Soup" style keywords – suggestions you get when you type a main keyword into the Google search bar and then add A, B, C, etc. This method can uncover many long-tail keywords.
Ahrefs' difficulty score: 0-10 is Easy, 11-30 is Medium, 31-70 is Hard, and 70+ is Very Hard. However, in actual testing, even terms marked as "medium-low" might have search results pages filled with high-authority sites. Therefore, tool data is always an aid, not a substitute for manual judgment.
This is a Chrome extension that allows you to see keyword data directly on the search results page without opening a separate website. After installation, every Google search will display search volume, related keyword suggestions in a sidebar, and even estimated traffic, word count, and keyword frequency for the ranking pages.
The only drawback is the lack of domain authority data; otherwise, it would be perfect. However, for quickly verifying search volume and getting inspiration, this extension is sufficiently practical.
WordStream's specialty lies in its integration of keyword API data from both Google and Bing. No account registration is required; you can access it at wordstream.com/keywords. After entering seed keywords, you can filter by industry category and region.
The CPC and competition data displayed by the tool are primarily for advertising purposes and have limited reference value for organic search SEO. However, in our actual tests, we found its search volume estimates for certain keywords to be surprisingly accurate.
In addition to entering keywords, you can also directly input a competitor's website URL, such as rankmath.com. The tool will then list all the keywords that the site ranks for and their search volumes. Although the free version only shows the first page results, this feature is quite sufficient for competitive analysis.
Visit searchvolume.io. This tool does only one thing: tells you the average monthly search volume for keywords, with no other information. Its interface is minimalist, allowing you to query multiple keywords at once (one per line). After selecting the target country, simply submit.
Although its functionality is single-focused, sometimes you just need a quick tool to verify search volume without being distracted by other data. It does its job with focus.
Google Keyword Planner is my most frequently used free tool, for a simple reason: first, it's the source data; most other tools obtain their data through Google's APIs; second, it's completely free and has no usage limits, requiring only a Google account.
Access it via the tools menu at ads.google.com, and find Keyword Planner under "Planning." You can use it even without running ads, but search volumes will be displayed as ranges (e.g., 100-1000) instead of precise numbers. If you run even a $1 ad campaign, you'll see exact data.
Click on "Discover new keywords," enter your seed terms, and then in the location filter, you can remove all pre-selected options to get global data – a feature rarely offered by other free tools. It can generate hundreds of related suggestions from a single seed term and allows you to set negative keywords, such as filtering out outdated years like "2021" or "2022."
The most powerful feature is URL analysis. Enter a competitor's page link, and the tool will list all the keywords that page ranks for. This is very useful during the content planning phase: you can see which keywords are covered by top-ranking pages and then optimize your own content strategy.
Sort the results by search volume from low to high, paying close attention to long-tail keywords with high competition. Although these terms have low search volume, they have high conversion value. If you monetize through display ads, ranking for these terms will bring better returns.
We tested all the tools with the keyword "Rank Math tutorial" and then compared it with 12 months of real data from Google Search Console. The monthly search volumes given by each tool were:
Our Search Console showed that the average monthly search volume for this term over 12 months was 124. The results are clear: WordStream and Google Keyword Planner are the tools closest to the real data. Considering both functionality and accuracy, Google Keyword Planner comes out on top.
AnswerThePublic used to be an essential tool for SEO professionals, but after being acquired, it was limited to 3 queries per day. The good news is that we've found an alternative – Answer Socrates (answersocrates.com), which integrates data from Google Suggest, People Also Ask, and Google Trends, with no query limits.
Enter a broad topic like "vertical farming," and the tool will list various questions real users ask on Google, phrases including prepositions, comparison keywords, and "alphabet soup" style suggestions. These are all angles you can expand into full blog chapters.
If your website already has some traffic, Google Search Console itself is the best source of keyword opportunities. Go to the "Performance" tab, click on a specific page, switch to the "Queries" view, and sort by impressions.
Pay close attention to keywords with high impressions but low click-through rates – this indicates that your page is already ranking, but your title or meta description is not compelling enough. Optimize existing pages or write new content targeting varying search intents; the conversion efficiency will be much higher than starting from scratch.
Different tools have different data sources, statistical periods, geographical scopes, and calculation methods. Google Keyword Planner uses data from the Google Ads platform, while WordStream integrates APIs from Google and Bing. Third-party tools may be based on scraping or estimation models. Differences are inevitable; the important thing is to understand the trend rather than getting hung up on specific numbers.
Keywords with a monthly search volume of 100-500, where 2-3 of the top 10 results have a DA below 40, and clear search intent long-tail keywords. Avoid brand terms and popular keywords monopolized by large sites; focus on niche scenarios and specific problems.
You don't need to use all of them, but a combination is recommended: use Google Keyword Planner to check search volumes and competitor keywords, Keyword Surfer for quick verification, and Answer Socrates to expand content ideas. Tools are aids; the core is understanding user needs and search intent.
Any tool's difficulty score is just an algorithmic estimate. The only reliable method is to search the term on Google and examine the Domain Authority, content quality, and page type of the top 10 results. If they are all in-depth content from major sites, the difficulty is high; if there are forum posts or Q&A pages, the opportunity is greater.
Paid tools offer more comprehensive competitive analysis (e.g., backlink counts, ranking history, SERP features), more granular data (e.g., precise search volume, click-through rate estimates), bulk operations, and API integration. However, for most small and medium-sized websites, the data from free tools is sufficient to support content decisions. The key is knowing how to use and analyze them.
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