Free Canonical Tag Checker

Our canonical tag checker fetches a page and reads exactly what it tells search engines about its canonical URL. Enter a URL and the tool extracts every rel="canonical" link tag and the og:url, resolves them to absolute URLs, and compares them to the page you actually requested. It then tells you whether the canonical is self-referencing (pointing at this page) or points somewhere else, and flags the problems that cause duplicate-content and indexing issues. The fetch runs on our server, so it works even when a page blocks browser requests.

It catches the canonical mistakes that quietly hurt rankings: a missing canonical, more than one canonical tag (especially ones that disagree), a relative instead of absolute href, an empty href, and an og:url that conflicts with the canonical. Every finding is based on the page's real markup, with no made-up score, just the concrete issues and what they mean.

For SEOs

Our tool answers "is this page canonicalized correctly?" in one check, so you can:

• Confirm an important page points to itself, not a duplicate
• Catch a canonical that accidentally sends signals to another URL
• Spot relative or duplicate canonicals that get ignored

For Developers

Our tool gives you a quick canonical audit, so you can:

• Verify a template outputs one absolute, correct canonical
• Check that canonical and og:url agree
• Debug indexing issues caused by the wrong canonical target

Why Use Our Canonical Tag Checker

• Reads the real page: It fetches and parses the live HTML, so you see the canonical search engines actually receive, including after a redirect, not what you assume is there.
• Catches the silent issues: Missing, multiple, relative, empty, or conflicting canonicals are all flagged, the kinds of mistakes that split ranking signals without any visible symptom.
• Clear, honest findings: Each result is labeled error, warning, or info with a plain explanation. There is no vague score, just what is set and whether it is correct.