Canonical Checker

Check your canonical tags

A wrong canonical can quietly deindex pages or split your ranking signals. Check your homepage's canonical instantly — no signup — then crawl every page.

Instant, free, no account needed — homepage checked on the spot.

What we check on your canonicals

The instant check reads your homepage's canonical. A full crawl checks every page's canonical against the rules below.

Canonical present

Every indexable page should declare a rel="canonical".

Self-referencing

The canonical should point to the page's own clean URL unless you intend otherwise.

Resolves to 200

The canonical target must be a live page — not a redirect or a 404.

Canonical-to-redirect

Flags canonicals that point at a URL which then redirects — a wasted signal.

HTTPS canonicals

Canonicals should use https, not leftover http after a migration.

Canonical changes over time

A full audit tracks pages whose canonical changed between crawls.

How to get canonical tags right

Canonicalisation is subtle but high-impact — these are the rules that keep your ranking signals where they belong.

1. Default to a self-referencing canonical

On every indexable page, add <link rel="canonical" href="THIS-PAGE-CLEAN-URL"> pointing to its own URL. This is the safe default and stops search engines guessing which of several similar URLs to index.

2. Make sure the target returns 200

The URL in your canonical must be live and canonical itself — not a redirect, not a 404. A canonical pointing at a redirected URL is ignored, and Google picks its own. Re-check after any HTTP→HTTPS or trailing-slash change.

3. Don't canonicalise pagination to page 1

A common template bug: every page in a paginated series canonicalises back to page 1, which deindexes pages 2+. Each paginated page should self-reference (or use proper pagination handling), not point to page 1.

4. Keep canonical, hreflang and internal links in agreement

Your canonical, your hreflang annotations, and the URLs you link internally should all point at the same canonical version. Mixed signals (linking to one URL but canonicalising to another) confuse crawlers.

5. Use canonicals to consolidate, not to hide

Canonical is a hint for consolidating duplicates — it is not a way to deindex a page (use noindex for that) or to block crawling (use robots.txt). Use the right tool for each job.

Canonical checker FAQ

What is a canonical tag?

A rel="canonical" tag tells search engines which URL is the preferred version when similar content exists at multiple URLs. It consolidates ranking signals onto one URL and prevents duplicate-content dilution.

Should every page have one?

Yes — a self-referencing canonical on every indexable page is the safe default, unless you deliberately want a page consolidated into another.

What is a canonical-to-redirect error?

When a canonical points at a URL that redirects or 404s. Google ignores it and picks its own canonical, wasting your signal. Every canonical must resolve to a live 200 URL.

Can I check canonicals across my whole site?

Yes. The instant check reads your homepage; run a full audit to check every page's canonical for self-reference, redirects and changes over time.

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