There's no shortage of tools purpose-built for keyword research (literally hundreds of them), and they run the gamut from beginner-focused to highly advanced. They also range from totally basic and unhelpful to super valuable.
When done right, the best keyword research tools simplify and streamline your workflow—they make it easier to find the right keywords to target and give you the data you need to actually rank for them. But they shouldn't require you to empty out your bank account and sell your first-born child in order to access that data.
After years of working with multiple clients who use all different tools for keyword research and SEO content optimization, I've seen the best (and the worst) of them—and I know how important it is to choose the right keyword planner tool. To help, I considered over 80 tools with a free option for keyword research. After in-depth testing, here are the four best free keyword research tools, including the all-around greats and apps built for more specific use cases.
The best free keyword research tools
Moz Keyword Explorer for the best all-around free SEO keyword research tool
Google Keyword Planner for researching paid keywords
Semrush for advanced SEO professionals
Free Keyword Research Tool for a simple tool
What makes the best keyword research tool?
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The features that make for a great keyword research tool are pretty straightforward: you search for a given keyword, and the tool tells you about it. But there are so many different ways to use keyword data, so I wanted to find tools that could handle a variety of use cases, along with a few designed for some of the most popular uses for keyword research.
During testing, I looked primarily at the factors below to determine which apps made the initial list.
Data included. The best keyword research tools give you all the data you need to rank for your chosen keyword. All of the apps I selected include, at minimum, traffic, keyword difficulty, and competitive SERP analysis.
Keyword optimization guidance. You shouldn't have to be a 10-year SEO industry veteran to use keyword research tools—the best tools offer simple, straightforward suggestions to optimize for your keywords. There are tools (like Ahrefs, Semrush, and Moz) that do complete SEO analysis on your site, checking for everything from site speed and technical details to domain authority and topic clusters. That's not what we're looking for here. We're looking for tools that any business owner or marketer can use to quickly understand their target keyword and optimize their site to rank for it.
Free plan allowances and upgrades. Some tools include super limited results for free and call it a "free plan." Or they put time limits on the free plan, effectively making it more of a trial. I only included tools with evergreen free plans generous enough to actually be useful—and they won't break the bank when it's time to upgrade, either. One of my favorite tools from last year, Ahrefs, didn't make the cut this year because its keyword research tools are no longer free.
Standalone functionality. Since you're looking for something free, your keyword tool should be a one-stop shop—without requiring any additional tools or extensions to work for you, especially not ones you'd have to pay for. And while I didn't consider them for this round-up, there are a number of great WordPress SEO plugins you can start using right away if you have a WordPress site.
To find the best of the best, I put each tool that checked those boxes to the test by running through an in-depth protocol. Here's what my testing workflow looked like:
If needed, I created an account and went through any provided onboarding or guided tutorials (many of these free apps don't require account creation or provide any onboarding).
I searched for a few different kinds of keywords—e.g., "free keyword research tools," "chocolate cake," and "best white sneakers"—to see the results for different search intent.
I checked which related keywords, metrics, and other data were offered. I also made note of the source, whether information was pulled from Google, included non-search engine websites (like social media or forums), or was drawn from the tool's own native data.
I verified allowances for the free plan—whether limited by time, number of results, metrics included, searches per day or month, or something else—and the cost to upgrade to a paid plan if needed.
Where available, I tested out additional keyword research tools like competitive gap analysis, content optimization features, and more.
After spending over a dozen hours with these apps this year, I landed on the four best keyword research tools—each with a manageable free version—below.
The best free keyword research tools at a glance
Best for | Standout feature | Free plan | |
|---|---|---|---|
An all-around solution | Keyword prioritization metrics | 10 queries per tool per month, with 1,000 keyword suggestions and 10 SERP analyses per query | |
Researching paid keywords | Forecasting features and budget planning | Completely free (but you get more out of it if you use Google Ads) | |
Advanced SEO professionals | Granular keyword data | 10 Analytics reports per day, 10 tracked keywords | |
Basic, simple keyword research | Suggested content angles | Completely free |
The best free keyword research tool overall
Moz Keyword Explorer (Web)
Moz pros:
More approachable data presentation than many other tools
Straightforward prioritization metrics
Broad set of tools available for free
Moz cons:
Less data than more robust tools
Free plan only includes 10 queries per tool per month
Moz's SEO platform offers several different tools designed for keyword research. While Moz doesn't include as many data points as some of the other full-featured SEO tools (like SERP position history or the total number of keywords a competing result ranks for), I'd consider that a benefit. It makes for a less overwhelming user experience for those who aren't professional search marketers, without skimping on the metrics you really want.
With the Keyword Explorer tool, you can search any keyword you choose and see its monthly volume, difficulty, and organic clickthrough rate (CTR). Scroll down from there to see an analysis of current results ranking for it and suggestions for similar keywords.
Metrics like straightforward keyword difficulty and minimum domain authority make it easy to prioritize the keywords you have the best chance to rank for—and avoid wasting your time on out-of-reach queries.
Plus, with the Keyword Gap feature (part of the Competitive Research tool), you can find all the keywords your competitors rank for that you don't.
Moz pricing: Keyword research features are available for free for up to 10 queries per tool per month with up to 1,000 keyword suggestions and 10 SERP analyses per query; Moz Pro plans start at $99/month for 150 keyword queries per month
The best free keyword research tool for paid keywords
Google Keyword Planner (Web)
Google Keyword Planner pros:
Completely free forever, even if you don't use Google Ads
Helpful forecasting features for budgeting if you do use Google Ads
Can pull keyword suggestions from just your website
Google Keyword Planner cons:
Not helpful for organic keyword research
When it comes to PPC keyword research, Google Keyword Planner is one of the best tools out there. It's completely free (even if you don't buy Google Ads), so you never have to worry about running into limits or expensive upgrades.
Google Keyword Planner includes two main features: one for exploratory keyword research and discovery and another for more in-depth research on search volume and forecasting.
The "Keyword ideas" feature is similar to many of the tools on this list: you search for a seed term, and it generates other keyword ideas, along with details on monthly search volume, change over time, competition, ad impression share, and bid ranges. You can refine your keyword list by brand or non-brand keywords, source website, and more. If you're also using Google Ads, the "Forecast" feature makes it easier to plan ahead for your paid ads and budget in advance.
Keyword Planner can inform your organic strategy, too, by showing you where ranking organically may help you save on PPC costs.
Google Keyword Planner pricing: Free
The best free keyword research tool for advanced SEO
Semrush (Web)
Semrush pros:
Tons of granular keyword data
Wide range of specialized keyword research tools
Pretty generous free plan
Semrush cons:
Can be overwhelming for those less experienced with keyword research
Most expensive upgrade
If you're looking for something more advanced, Semrush shares a ton of keyword data and makes it easy to dig into the details, like SERP features (featured snippet, reviews, site links, image pack, and so on) and granular analysis of current results. Semrush offers a broad range of keyword research tools, too, from the standard traffic and search volume data to content-driven keyword research and competitive keyword gap analysis.
That range is what really sets Semrush apart, including the standard Keyword Overview, the Keyword Magic Tool for exploratory keyword research, a Keyword Manager and position tracking, competitive Keyword Gap analysis, and Organic Traffic Insights, which—when connected with your Google Analytics or Search Console account—can uncover those famously tricky "not provided" keywords.
As an added bonus, the SEO Content Template tool lets you automatically create a content brief and optimize content as you write by grading your content in real-time for readability, originality, tone of voice, and SEO: it uses a handy bullseye graphic to help you strike the right balance. Plus, the tool visually checks off SEO recommendations (like using your target and related keywords and adding relevant links and images) as you go.
The app's newly released Copilot AI will even make proactive recommendations: flagging when your rankings drop for tracked keywords, for example, making technical SEO recommendations, and prompting you to add additional information to help fine-tune your data.
All of this means that upgrading will cost you a pretty penny—but you can use it for free at low volumes to start.
You can do more with Semrush by connecting with Zapier to keep track of SEO tasks across Semrush and your project management tool, automate site audits and re-crawls, connect with Google Analytics goals, and more. Here are some examples.
Send Slack channel messages for completed SEMrush site audits
Generate overview reports in SEMrush when site audits are completed in SEMrush
Create Notion database items for new SEMrush Site Audit tasks.
Semrush pricing: Free plan includes up to 10 Analytics reports per day and 10 tracked keywords; paid plans start at $129.95/month for up to 10,000 results per report and 500 tracked keywords per month.
The best simple and free keyword research tool
Free Keyword Research Tool (Web)
Free Keyword Research Tool pros:
Simple, straightforward report
Unique suggested content angles
Free Keyword Research Tool cons:
Very basic data
No built-in way to save your research
If you're looking for a straightforward tool to give you basic data on keywords, Ryan Robinson's Free Keyword Research Tool is a super simple option.
The Explorer tab pulls up related queries for any keyword you search, along with ballpark search volume numbers and a keyword difficulty characterization from "low" to "very high." My favorite feature here is the suggested angles you can use to build content. Tab over to the Ideas tab (or click the lightbulb icon on any of the related keywords) to see suggested long-form versions of the keyword that can help inform your content angle.
That's… pretty much all there is here. You can't get a ton of data from this tool—and there's no upgrade option for when you're ready to financially invest in your search strategy. But if basic keyword research is all you really need, it's worth a look.
Free Keyword Research Tool pricing: 100% free
Can you use AI chatbots for keyword research?
You can ask AI chatbots like ChatGPT and Gemini (formerly Bard) to do keyword research for you—but should you?
The main benefit of going the AI route is simplicity. You can ask for straightforward, simplified results and get a simple, streamlined answer.
Here's Gemini, for example.
And here's ChatGPT.
ChatGPT was more upfront about the sources it used (in the screenshot above, for example, you could click on "Searched 7 sites" to see the specific websites the chatbot referenced). But it also offered search volume numbers—which seems impressive, if it weren't for the fact that I know it's making it up. ChatGPT isn't able to read real-time data (it'll even admit this itself if you ask). Gemini was more transparent: it told me it couldn't pull precise monthly search volume numbers (it's not even connected to Google Keyword Planner), and it only told me the type of content it expects to rank for that keyword—not the actual content that's currently ranking.
I'll admit, both ChatGPT and Gemini have improved a lot since last year, especially when it comes to more complex prompts. That said, the information they provided still falls short of the utility you get from a tool that's actually designed for keyword research. For now, at least.
If you're in a bind and need simplified, bottom line-style information on a keyword quickly, an AI chatbot may be of some help. But as of today, I wouldn't recommend using AI chatbot as your primary keyword research tool—especially given the number of truly helpful dedicated free keyword research tools you can use instead.
Of course, lots of dedicated SEO tools (though usually not the free ones), will have AI built in—that's the best of both worlds.
When should you upgrade from a free keyword research tool?
The short answer is: only when you need to. If you can get all the data you need without going over the allowances of one of the free plans above, there's no reason to upgrade to a paid plan (or switch to a fully paid tool).
With that said, here are a few signs it may be time to consider upgrading:
You're regularly hitting the monthly or daily search limits of your current solution.
You're missing out on features you can't get for free, like content optimization guidance or the ability to track your site's keywords and rankings over time.
You need additional SEO features that an upgraded all-in-one tool can provide (like technical SEO, site auditing, etc).
When the time comes, some of the tools on this list can grow right along with you. Moz Pro is a super robust tool, for example, as is Semrush. There are also a number of popular tools with affordable starting plans, including GetKeywords, KWFinder, and Topic Ranker.
Here are Zapier's lists of helpful SEO tools to get you started:
Related reading:
This article was originally published in June 2021. The most recent update was in May 2024.
