Best Free Keyword Research Tools 2026: 6 Options Compared
Best free Keyword Research Tools compared: Ahrefs, Google Search Console, Google Keyword Planner, Google Trends and 2 more, with free-plan limits, platforms and prices from official pages checked October 24, 2026.
•3 min read•SEO Tools
Quick comparison
| Tool | Price | Platforms | Best for | Tested |
|---|---|---|---|---|
| Ahrefs | Free (Ahrefs Free: unlimited verified sites, Site Audit 5K crawl credits per project per month, Site Explorer shows up to 1K backlinks and keywords); paid from $29 per month (Starter; Lite is $129 monthly) | Web browser | Fresh ideas and difficulty checks | Docs only |
| Google Search Console | Free (Free service; Google states no usage plans) | Web browser | Improving pages you already have | Docs only |
| Google Keyword Planner | Free (Free to use per third-party sources; Google says basic features need a Google Ads account with billing information entered) | Web browser | Checking search volumes before writing | Docs only |
| Google Trends | Free (Shows relative search interest (index with 100 as peak) for up to five terms at once; Google presents it as a free-to-use aid and states no price) | Web browser | Comparing two phrasings or checking timing | Docs only |
| Semrush | Free (1 demo project, 10 reports per day across tools); paid from $139 per month, billed monthly (SEO plan; $117.33 billed annually) | Web browser | A taste of a full SEO suite | Docs only |
| Keyword Tool | Free (Free plan shows keyword suggestions and some data with no account needed) | Web | YouTube and video keyword ideas | Docs only |
Independent comparison. Paid placements are labelled separately; editorial links earn no affiliate commissions. Learn more.
Good fit if
- You want to improve pages that already get impressions (Google Search Console is the pick)
- You need ideas for a brand-new topic (Ahrefs is the pick)
- You are choosing between two names for something (Google Trends is the pick)
- You make YouTube videos (Keyword Tool is the pick)
Not ideal if
- You need paid-tier features, uptime guarantees or support that these free plans leave out
Free keyword research tools split into two types: tools that show demand for terms you type in, and tools that report what your own site already ranks for. Google Search Console is the second kind. It lists the queries that brought impressions and clicks to your verified site, which is the most reliable keyword data you can get for free, though only for terms you already appear for. Ahrefs and Semrush are the first kind and give a taste of their paid indexes: Ahrefs' free tools include a keyword generator and difficulty checker, and Semrush's free account allows ten reports a day on one demo project. Google Keyword Planner reports volume ranges but sits inside Google Ads, and Google says basic features need account setup with billing details, so expect friction. Google Trends does not give volume at all; it shows relative interest on a 0 to 100 scale for up to five terms, which is useful for seasonality and for choosing between two phrasings. Keyword Tool reads YouTube autocomplete, so it fits video titles better than blog posts. Use a free stack: Search Console for existing pages, Trends for timing, and a free generator for new ideas. Judge difficulty yourself by reading the top results.
Ahrefs
Free keyword generator and difficulty checker for any term, and Ahrefs Free shows up to 1,000 keywords on a verified site. Deeper data needs a paid plan from $29 a month.
Price: Free (Ahrefs Free: unlimited verified sites, Site Audit 5K crawl credits per project per month, Site Explorer shows up to 1K backlinks and keywords); paid from $29 per month (Starter; Lite is $129 monthly) (Ahrefs pricing, checked 2026-10-22).
Platforms and license: Web browser. Proprietary SaaS.
Best for: Fresh ideas and difficulty checks.
Compare: Ahrefs alternatives
Google Search Console
Shows the real queries, clicks and impressions for your verified site at no charge. It cannot show data for terms you do not yet rank for.
Price: Free (Free service; Google states no usage plans) (Google Search Console pricing, checked 2026-10-22).
Platforms and license: Web browser. Proprietary free service.
Best for: Improving pages you already have.
Worth knowing: Covers your own verified sites only, not competitors.
Google Keyword Planner
Free to use according to third-party guides, but Google says basic features require a Google Ads account with billing information entered. Useful for volume ranges.
Price: Free (Free to use per third-party sources; Google says basic features need a Google Ads account with billing information entered) (Google Keyword Planner pricing, checked 2026-10-24).
Platforms and license: Web browser. Proprietary free tool.
Best for: Checking search volumes before writing.
Google Trends
Relative search interest on a 0 to 100 scale for up to five terms, good for seasonality and comparing phrases. It does not report absolute volume.
Price: Free (Shows relative search interest (index with 100 as peak) for up to five terms at once; Google presents it as a free-to-use aid and states no price) (Google Trends pricing, checked 2026-10-24).
Platforms and license: Web browser. Proprietary free service.
Best for: Comparing two phrasings or checking timing.
Semrush
Free account gives one demo project and 10 reports a day across tools. Paid SEO is $139 a month billed monthly, so most users stay on the free sample.
Price: Free (1 demo project, 10 reports per day across tools); paid from $139 per month, billed monthly (SEO plan; $117.33 billed annually) (Semrush pricing, checked 2026-10-22).
Platforms and license: Web browser. Proprietary SaaS.
Best for: A taste of a full SEO suite.
Worth knowing: 7-day trial of paid plans.
Compare: Semrush alternatives
Keyword Tool
Free plan shows keyword suggestions with no account, taken from YouTube autocomplete. Search volume, CPC and competition need the Pro plan.
Price: Free (Free plan shows keyword suggestions and some data with no account needed) (Keyword Tool pricing, checked 2026-10-22).
Platforms and license: Web. Proprietary.
Best for: YouTube and video keyword ideas.
Which one to pick
- You want to improve pages that already get impressions: Google Search Console
- You need ideas for a brand-new topic: Ahrefs
- You are choosing between two names for something: Google Trends
- You make YouTube videos: Keyword Tool
Limits of this review
Docs-only for Ahrefs, Google Search Console, Google Keyword Planner, Google Trends, Semrush, Keyword Tool: we did not install or run them, so feature claims come from vendor pages. Vendor prices and free limits change; confirm on the linked pricing page before you commit.
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Kevin Fan
Kevin Fan is a SaaS founder. He runs Free Instead Of, which tracks free and open-source alternatives to paid software and checks each price and free-plan limit against the vendor's own pages.
Methodology
Based on official pricing, license and product pages checked between 2026-10-22 and 2026-10-24: Ahrefs, Google Search Console, Google Keyword Planner, Google Trends, Semrush, Keyword Tool. Prices, free limits and licenses are the figures shown on those pages on those dates. No tool on this page was installed or run. No accounts were created.