What Is a Canonical Tag?
A canonical tag (rel="canonical") is an HTML element that tells search engines which URL is the authoritative version of a page when the same or similar content is reachable at more than one address. It's a signal Google generally respects but doesn't always follow exactly as specified.
When do you actually need one?
Duplicate or near-duplicate content is more common than most site owners realize: a product page reachable with and without tracking parameters, the same article syndicated to a partner site, or a URL accessible via both www and non-www versions. Without a canonical tag, search engines have to guess which version to index and may split ranking signals across duplicates instead of consolidating them.
Set the canonical tag on every duplicate or near-duplicate URL, pointing to the one version you want indexed and ranked.
PUT THE CLAIM ON THE RECORD
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