Free SERP Similarity Checker
Compare live Google search results for up to 3 keywords and see exactly how much they overlap. Decide in seconds whether keywords belong on one page or separate pages, and stop keyword cannibalization before it costs you rankings.
Free forever · No signup · Live Google data · 76 countries · Trusted by 40,000+ SEO professionals
What is SERP similarity?
SERP similarity measures how many of the same URLs appear in Google's top results for two or more keywords. Google's rankings are the most honest signal of search intent you can get: when two keywords return mostly the same pages, Google is telling you it considers them the same topic. When the results barely overlap, Google sees two different intents, and no single page will rank well for both.
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Keyword clustering
Group keywords that share intent so one strong page targets the whole cluster instead of several weak ones.
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Stop cannibalization
Spot keywords your existing pages are fighting over, and consolidate before your rankings split.
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Plan content with proof
Replace gut feel with live SERP evidence when deciding what deserves its own page.
How the similarity score is calculated
For each keyword we fetch the live top 10 organic results from Google for your chosen country and language. URLs are normalized (protocol, www, trailing slashes and tracking parameters are ignored), then every pair of keywords is scored with the overlap coefficient: shared URLs divided by the size of the smaller result set. Six shared URLs out of ten means 60% similarity. Exact URL matches drive the score; same-domain matches are shown separately as a weaker signal.
| Score | What it means | What to do |
|---|---|---|
| 71-100% | Same search intent | Target all keywords on one comprehensive page |
| 31-70% | Strongly related intent | Likely one page; review the shared URLs to confirm |
| 1-30% | Mostly different intent | Lean toward separate pages; use judgment on the topic |
| 0% | Completely different intent | Create a dedicated page per keyword |
Built for real SEO workflows
Live SERP data
Every check queries Google in real time. No stale exports, no week-old cached rankings.
3-keyword comparison
Most free tools stop at 2 keywords. Compare 3 at once and see every pairwise score.
76 countries, 36 languages
Uses the right Google domain and geo parameters, so you analyze the SERP your audience actually sees.
Visual overlap analysis
Side-by-side SERPs with shared URLs highlighted, plus an overlap table you can read at a glance.
CSV export
Download the full overlap table for client reports, content briefs or your keyword map.
Free, no signup
No account, no email, no credit card. Open the page, paste your keywords, get an answer.
How to use the SERP similarity checker
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Enter your keywords
Add 2 or 3 keywords you are considering targeting. Pick variants that feel related, for example "best crm software", "top crm tools" and "crm platforms".
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Select location and language
SERPs differ dramatically between markets. Choose the country and language your audience searches in to get results that match reality.
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Run the analysis
The tool fetches the live top 10 for each keyword in parallel and scores every keyword pair. You will see progress as each SERP arrives.
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Act on the recommendation
Follow the verdict: combine keywords on one page at high similarity, split them at low similarity, and manually review the shared URLs in between. Export the CSV for your content plan.
How we compare to other SERP similarity tools
| Feature | SERP SimilarityThis tool | Thruuu | Optiwing | SEO Growth Notes |
|---|---|---|---|---|
| Keywords compared | 3 keywords | 2 keywords | 2 keywords | 3 keywords |
| Pricing | Free forever | From $19/month | From $10/month | Free (limited offer) |
| Signup required | No signup | Yes | Yes | Yes |
| Multi-location | Yes, 76 countries | Yes | Yes | Yes |
| Visualization | Yes | No | Yes | Yes |
| Smart recommendation | Yes | Yes | No | Priority score |
Frequently asked questions
What is SERP similarity?
SERP similarity measures how many of the same URLs rank in Google's top results for two or more different keywords. When keywords share many ranking URLs, Google treats them as having the same search intent, which usually means one page can rank for all of them. When they share few or none, Google sees different intents and each keyword deserves its own page.
What is a good SERP similarity score?
There is no single "good" score; it depends on your goal. As a rule of thumb: 71-100% means the keywords share the same intent and belong on one page, 31-70% means they probably belong together but you should manually review the overlapping results, 1-30% means they likely need separate pages, and 0% means completely different intents and definitely separate pages.
How is the SERP similarity score calculated?
The tool fetches the top 10 organic Google results for each keyword, normalizes the URLs, and counts how many exact URLs the two SERPs share. The score is the number of shared URLs divided by the size of the smaller result set, expressed as a percentage. For example, if two keywords share 6 of their top 10 URLs, the similarity is 60%.
Should I target similar keywords on one page or separate pages?
Let the SERP decide. If Google ranks mostly the same URLs for both keywords (high similarity), one well-optimized page can capture both. If Google ranks different URLs (low similarity), it interprets the intents as different and you will need a dedicated page per keyword to compete.
How does SERP similarity help find keyword cannibalization?
If two keywords you target on separate pages show high SERP similarity, those pages are competing for the same intent, which is the classic setup for keyword cannibalization. Consolidating them into one stronger page usually improves rankings. Run your suspected keyword pairs through this tool to confirm before merging.
How fresh is the SERP data?
Results come from a real-time SERP API that queries Google when you run the analysis, so you see the live top 10 for your chosen country and language. Identical queries are briefly cached for a few minutes to keep the tool fast and free.
Can I compare keywords in different countries and languages?
Yes. The tool supports 76 countries using the matching Google domain and geolocation parameters, and 36 interface languages, so you can check similarity exactly as your target audience sees the results.
Is the SERP similarity checker really free?
Yes, it is completely free with no signup, no email, and no credit card. You can run as many checks as you like within fair use. If you need more, such as comparing up to 6 keywords, search history, or city-level locations, the advanced version inside Keyword Insights covers that.
What is the difference between an exact URL match and a domain match?
An exact URL match means the very same page ranks for both keywords, which is the strongest signal of shared intent and is what the similarity score counts. A domain match means the same website ranks with different pages, which suggests the topics are related but distinct enough that the site targets them separately. The results view marks both so you can judge intent precisely.
Need more than 3 keywords?
The advanced SERP similarity checker inside Keyword Insights compares up to 6 keywords, keeps your search history, adds city and state-level locations, search intent data and unlimited checks. It is included on every plan.
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