Canonical Tag Checker

A canonical tag checker reads the canonical URL a page declares and compares it with the address you tested. The canonical tells search engines which version to index when similar URLs exist.

This tool fetches the address you enter once, from our server, and reports what a crawler would receive. The URL is not stored; only a short-lived rate-limit counter is kept. Results show the page at the moment of the check and can differ from what a logged-in browser or a bot with different headers sees.

How to read the result and act on it

Compare the declared canonical with the tested URL. For most indexable pages they should match exactly, including protocol, host, path and trailing slash. If the canonical points elsewhere, ask whether that is deliberate, as with a parameter or duplicate version that should consolidate onto a main page. Make sure the canonical target returns a 200, is indexable, and is not itself canonicalised to another URL. Use absolute URLs rather than relative ones to avoid ambiguity. If no canonical is found, add a self-referencing one on pages that can be reached by several URLs. After changes, confirm the tag sits in the head of the raw HTML, not injected later by script.

Common mistakes to avoid

Typical errors include canonicals pointing to a redirected or 404 URL, canonicalising paginated pages all to page one, and copying a template so every page declares the homepage as canonical. Mixing http and https, or www and non-www, between the canonical and the live address creates conflicting signals. Placing the tag in the body rather than the head makes it likely to be ignored. Do not combine a canonical to one URL with a noindex on the same page, since the signals contradict each other. Remember that a canonical is a hint, not a command, so also fix duplicate content at the source with redirects where possible.

What is a canonical tag?

A link element in the head that names the preferred URL for a page, used to consolidate duplicate or similar URLs.

Should every page canonicalise to itself?

Yes, self-referencing canonicals are a good default unless the page is a duplicate of another.

Does Google always obey canonical tags?

No. It treats the tag as a strong hint and may choose a different canonical if other signals conflict.

How do I check which canonical URL Google chose?

Use the URL Inspection tool in Search Console, which shows the user-declared canonical and the Google-selected canonical. If they differ, look for stronger signals pointing to another URL, such as internal links, redirects or sitemap entries.

Should canonical tags be absolute or relative URLs?

Absolute URLs are recommended. Relative paths are allowed but can be misread if the page is served on several hosts or the base URL changes. A full URL with protocol and host removes that ambiguity.

• Indexability Checker: Run all indexing checks on a URL: status, redirects, robots rules, meta robots, headers and canonical.
• Noindex Checker: Check whether a URL is blocked from indexing by a meta robots tag or X-Robots-Tag header.
• Redirect Checker: Trace every redirect hop from a URL to its final destination, with status codes.

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