Is Google indexing the wrong version of your pages?

When several URLs serve the same page, a canonical tag is how you tell search engines which one to keep. Missing, wrong or cross-domain canonicals quietly split your ranking across duplicates.

Reads the canonical tag on a sample of key pages and compares it against the page URL. Nothing is stored.

How this check works

Shipwork fetches a sample of your key pages and reads each one's canonical declaration. It flags pages with no canonical, canonicals pointing at a different domain, and canonicals that resolve to a different URL than the page itself — each of which can move ranking away from the page you meant.

Questions

What is a canonical tag?
A link element that names the preferred URL for a page. It tells search engines which version to index when duplicates exist.
Should the canonical point to itself?
Usually yes — a self-referencing canonical is the safe default. It prevents variants (parameters, trailing slashes) being treated as separate pages.
When is a cross-domain canonical wrong?
Almost always, unless you deliberately syndicate content. Pointing your canonical at another domain tells Google to credit that domain instead of yours.

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