k-o.pro

Canonical Checker

Fetch canonical tag, og:url, and x-default hreflang from any URL — and flag the inconsistencies.

What it checks

Three signals that should all point to the same canonical URL:

  • rel="canonical" — tells Google which URL should rank
  • og:url — tells Facebook/social platforms which URL to attribute shares to
  • x-default hreflang — the fallback URL for users with no matching locale

When they don't match

A canonical pointing to /page-a while og:url points to /page-b splits link equity and social share counts between two URLs. Google ranks one; Facebook credits the other. This is common after migrations and quietly costs you.

How to use it

  1. Enter the URL you want to check
  2. Review the three tag values and the self-reference status
  3. Check the Issues panel — any mismatch between canonical and og:url is flagged
  4. Fix the mismatch at the template level, then re-run on a sample of your key pages

When to run it

On every URL you're actively acquiring links to — you want links credited to the right page. After publishing syndicated content anywhere. During a technical audit when you suspect duplicate content. After every CMS migration — canonical misconfigurations are one of the most consistent post-migration side effects.

Frequently asked questions

Is this canonical checker free?

Yes. It runs in your browser with no signup and no limits.

What should a canonical tag point to?

Usually the page itself, a self-referencing canonical, unless the page is a deliberate duplicate of another URL that should rank in its place.

Does a canonical tag guarantee indexing?

No. It is a strong signal, not a directive. Google can still pick a different canonical when your other signals, like internal links, sitemaps, and redirects, point elsewhere.

Related tools: hreflang checker, Google index checker, and bulk redirect checker. Background reading: keyword cannibalization.