Canonical URL Checker

Enter any URL to check its canonical tag. Detect missing, duplicate, or mismatched canonicals.

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AI Search Insights for Canonical Tags

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Canonicals consolidate AI citation authority

When multiple URLs serve the same content, AI engines may split citations across them. A canonical tag tells them which URL to cite — consolidating all authority signals (backlinks, engagement) into one URL that's more likely to appear in AI answers.

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Missing canonicals confuse AI crawlers

Without a canonical tag, AI engines must guess which version of a page is primary. This is especially problematic for sites with URL parameters, trailing slashes, or www/non-www variants. Every page should have a self-referencing canonical at minimum.

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Canonical must be absolute URL

Relative canonical URLs (/blog/post instead of https://example.com/blog/post) can cause parsing errors. AI crawlers processing pages at scale may misresolve relative URLs. Always use absolute URLs in canonical tags for maximum compatibility.

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What this canonical URL checker does

Enter a URL and this free tool finds its canonical tag, follows redirects, and tells you whether the page points to itself or somewhere else — so you can catch duplicate-content and indexing problems before Google does.

Why canonical tags matter

Duplicate content: a canonical tells Google which version of near-identical pages to index (e.g. with and without www, or with tracking parameters).
Self-referencing: most pages should point their canonical at themselves.
Wrong canonical: pointing to the wrong URL can deindex the page — this tool flags mismatches.

Frequently asked questions

What is a canonical tag?

A rel="canonical" link in a page's head that tells search engines which URL is the main version to index when several pages are the same or very similar.

Should a page be its own canonical?

Usually yes. Most pages should have a self-referencing canonical. Point it elsewhere only when the page is a genuine duplicate of another.

How do I check a page's canonical URL?

Enter the URL above; this tool fetches the page, reads its canonical tag, follows any redirects, and shows whether it is self-referencing or points elsewhere.

Is this canonical checker free?

Yes, it's free, needs no sign-up, and runs in your browser.

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