Duplicate Content Checker
Crawl your site and find pages with the same or nearly the same text: similarity per pair, duplicate groups, thin template pages and what canonicals handle.
Something not working, or missing a feature? Send feedback
About the Duplicate Content Checker
The Duplicate Content Checker finds pages on your own site that say the same thing. It crawls up to 100 pages from internal links and reads the main text of each, without the menu, header and footer. It also removes text that most pages share, then compares every page with every other. Pairs above your threshold are listed with their similarity and overlap and grouped into clusters. Pairs where a canonical tag or noindex already tells Google which page to index are shown as handled. A table shows how much of each page is unique.
Our server requests the URLs you enter, like a crawler: it reads the response without running the page's scripts, and the analysis runs in your browser. The URLs and results are not stored. Page texts are compared in your browser.
How to use the Duplicate Content Checker
- Enter the home page (or a section) and choose how many pages to crawl.
- Pick the similarity that counts as a duplicate: 80% suits most sites, 70% finds rewrites.
- Work through the duplicate groups: merge with a 301 redirect, set a canonical, or rewrite.
- Check the pages with almost no text of their own: thin tag and archive pages are often the cause.
Works well with the Duplicate Content Checker
- Site Audit Tool: find duplicate titles and other crawl issues.
- Bulk Meta Tag Extractor: check the canonicals of the duplicates.
- Text & Code Diff: compare two pages word by word.
Frequently asked questions
Does Google penalise duplicate content?
Not for ordinary duplication on your own site. Google picks one version to show and filters the others. The real cost is that the pages compete, links and signals are split, and Google may index the version you did not want. Copying other sites to manipulate rankings is a different matter (spam).
Does it check other websites for copies of my text?
No. It compares the pages of one site with each other. Finding copies elsewhere needs a web-scale index (a plagiarism checker such as Copyscape).
How is similarity measured?
Each page's text is split into overlapping five-word phrases. Similarity is the share of phrases two pages have in common (the Jaccard index); overlap is how much of the shorter page appears in the longer one, which catches a short page copied into a long one.
Related tools
Website SEO Checker
Check any page for on-page SEO problems: title, meta description, headings, canonical, robots.txt, noindex, structured data, alt text, HTTPS and speed, with a score.
Broken Link Checker
Find broken links on any web page: every internal and external link (and optionally image) is checked for 404s, server errors, timeouts and redirects. Export a CSV.
Redirect Checker
Check the HTTP status code and full redirect chain of up to 100 URLs: 301, 302, 404 and 5xx, response headers, loops and HTTPS downgrades, with fixes and CSV.
HTTP Status Checker
Check the HTTP status code of up to 100 URLs: 200, 301, 404, 500 and more, with what each means for SEO and a searchable list of every status code.
AdSense Readiness Checker
Check if your site is ready for Google AdSense: privacy policy, About and Contact pages, ads.txt, crawler access, thin pages, content risks and consent, before you apply.
Site Audit Tool
Crawl your website (up to 100 pages) and find broken pages, duplicate titles and descriptions, missing H1s, redirects, noindex, thin and slow pages. Export a CSV.