// free tool //
Canonical Tag Checker
See which URL a page tells Google to index, where that instruction comes from, and whether the canonical URL actually works. Checks the HTML tag and the HTTP Link header, then follows the canonical to test its status, redirects and noindex. Free, no account needed.
What a canonical tag does, and how it goes wrong
A canonical tells search engines which URL is the main version of a page. When the same content is reachable at several addresses - with tracking parameters, filters, a trailing slash or a www prefix - the rel="canonical" link says which one should appear in results and collect the ranking signals. It can sit in the HTML <head> or arrive as an HTTP Link header, and Google treats it as a strong hint rather than a command.
The common mistakes are quiet ones. Two plugins each add a tag and they disagree. The HTML says one URL and the server header says another. A template hardcodes the homepage as the canonical for every page, or points at the http:// version after a move to https. A canonical names a URL that redirects, returns 404 or is itself noindex, which gives Google contradictory instructions. This checker reports each of these, along with relative URLs and tags placed in the <body>, where Google ignores them.
A canonical is one of several signals that decide whether a page shows up in search. To check the others, use the Noindex Checker for robots meta tags, X-Robots-Tag headers and robots.txt, and the Redirect Chain Checker to see every hop between a URL and where it ends up.
Canonicals change without anyone noticing. Get told when they do.
This check covers today. MyKavo records the canonical on each page you monitor every scan and sends a high-severity alert, with the previous and current value, when it changes or disappears.
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- Monitoring in minutes
// questions //
Frequently asked questions
How do I check the canonical tag of a page?
Enter the URL and the checker reads every rel="canonical" declaration the page sends, both the <link> tag in the HTML and the HTTP Link header. If the canonical points to a different URL, it then fetches that URL and reports its status code, any redirects, whether it is noindex and what its own canonical says.
What happens if a page has more than one canonical tag?
When a page declares canonicals that point to different URLs, Google may ignore all of them and choose a canonical itself. The same applies when the HTML tag and the HTTP Link header disagree. Duplicate tags that agree are not a conflict, but they usually mean a theme and a plugin both add one, so keeping a single tag is safer.
Should a canonical tag point to the page itself?
Yes, for most pages a self-referencing canonical is correct. A canonical should only point elsewhere when this page is a duplicate or near-duplicate of that URL, such as a filtered or tracking-parameter version. The target should return 200 directly, without redirects, and must not be noindex.
What can't this canonical checker see?
It reads the HTML the server delivers and does not run JavaScript, so a canonical added only by client-side scripts will not appear. It checks public pages only, follows the canonical one step rather than through a whole chain, and reports what the page declares, not which URL Google finally chose. Search Console's URL Inspection shows Google's choice.