Canonical URL
A canonical URL is the address a site declares to be the authoritative version of a page, using a link element with rel=canonical.
Why it matters
Without one, a page reachable at several URLs competes with itself and its ranking signals split across the variants.
How it is measured
Fetch the page and read the canonical value: the href of the link rel=canonical element. On a healthy page the canonical value is absolute and points at the requested URL.
Checks that involve canonical url
Related terms
Questions
What is canonical url?
A canonical URL is the address a site declares to be the authoritative version of a page, using a link element with rel=canonical.
Why does canonical url matter?
Without one, a page reachable at several URLs competes with itself and its ranking signals split across the variants.
How is canonical url measured?
Fetch the page and read the canonical value: the href of the link rel=canonical element. On a healthy page the canonical value is absolute and points at the requested URL.