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Canonical Tag Checker

Check a page's canonical tag — the URL Google is told to rank.

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Updated Sep 2026

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How to use Canonical Tag Checker

  1. Enter the page URL and click “Check Canonical”.
  2. Compare the canonical to the page's own URL — self-referencing is correct for normal pages.
  3. Investigate mismatches: pointing at the homepage, another domain, or a redirecting/404 URL are bugs to fix in the template or plugin.
  4. Audit after migrations and plugin updates — the two events that silently rewrite canonicals sitewide.

What is Canonical Tag Checker?

A canonical tag checker fetches a page and reads its <link rel="canonical" href="…"> — the tag that tells search engines which URL is the authoritative version when the same content lives at several addresses (http/https, www/non-www, trailing slashes, tracking parameters, print views).

The tag concentrates ranking signals onto one URL instead of splitting them across duplicates. Its power is also its danger: a canonical pointing at the wrong page tells Google "rank that one instead of me" — and Google largely obeys. Wrong canonicals are among the quietest catastrophic SEO bugs: the page looks perfect in a browser while search sends every signal elsewhere.

About the Canonical Tag Checker

Enter a URL, click Check Canonical, and see exactly what canonical the page serves — and whether it's self-referencing (correct for most pages), pointing elsewhere (correct only for true duplicates), missing, or broken.

The bug catalog this catches: every page canonicalizing to the homepage (a misconfigured plugin — deep pages surrender their rankings to the front page); canonicals to the staging or http domain after a migration; canonicals to redirect or 404 targets (a contradiction Google resolves by ignoring or worse); and mixed signals where hreflang, sitemap and canonical disagree about the preferred URL.

The rule for healthy sites: every indexable page carries a self-referencing canonical — its own clean, absolute, https URL — and only genuine duplicates point elsewhere. Check key templates after migrations, plugin updates and domain changes; that's when canonicals silently break.

Frequently Asked Questions

Itself — the page's own clean, absolute, https URL. Self-referencing canonicals are the standard for every indexable page; only true duplicates (parameter versions, syndicated copies) point at a different URL.
Google is told to credit and rank that other URL — so your page's signals transfer away and it can drop from results entirely. Sitewide canonical-to-homepage is the classic version: every deep page quietly de-ranks itself.
A strong hint, not a command — Google can override it when other signals disagree (internal links, sitemap, redirects pointing elsewhere). Consistency across all signals is what makes canonicals stick.
Redirect when the duplicate URL shouldn't be visited at all (old address after a move). Canonical when both URLs must keep working but one should rank (tracking-parameter versions, printable views, A/B variants).
Yes in practice — relative canonicals invite protocol/host ambiguity and are a known source of bugs. Always the full https://www.example.com/page form, matching your true canonical domain exactly.

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