Glossary

Canonical Tag

A canonical tag tells search engines which version of a duplicate or similar page is the primary one to index.

A canonical tag (rel=canonical) is an HTML link element that names the preferred URL when the same or similar content exists at multiple URLs. It consolidates ranking signals onto one page and prevents duplicate-content dilution.

Example

An ecommerce product reachable via several category paths uses a canonical tag pointing every version to one clean product URL.