Checks
Duplicate content
Detects pages that serve byte-identical content under a content hash comparison, a stronger duplicate signal than matching titles or descriptions alone.
What this check looks for
Every successfully-crawled page carries a content hash computed by the crawler. This check groups pages by that hash and fails every page belonging to a group of two or more — each failure lists the other URLs sharing its exact content. A site where every page's content hash is unique passes.
Why it matters
When two URLs serve identical content, search engines have to choose which one to index and rank, and any links, shares, or authority pointed at the "losing" URL are effectively wasted since they don't consolidate onto the version that gets shown. This commonly happens with printer-friendly versions, session-parameter variants, staging copies left accidentally crawlable, or the same product reachable through two category paths. AI systems crawling multiple duplicate URLs waste crawl budget re-processing the same text and, worse, may cite whichever duplicate happens to rank or load first rather than the URL you'd actually want credited.
How to fix it
Pick one canonical URL per piece of content and consolidate the rest:
<!-- On the duplicate URL, point back to the original -->
<link rel="canonical" href="https://www.acme.com/headphones/wireless-nc">If the duplicate serves no independent purpose (an old parameter format, a legacy path), a permanent redirect is stronger than a canonical:
301 https://www.acme.com/headphones-old -> https://www.acme.com/headphones/wireless-ncFix the underlying cause too — check whether your CMS is generating parallel URL structures for the same content by default.
See how your site scores on this check