How to Set a Canonical URL

The same page is often reachable at more than one address: with and without www, with a trailing slash, with tracking parameters, over http and https. Search engines see each as a separate page and split the ranking between them. A canonical tag tells them which one counts.

Pick the one true URL for each page

Decide on a single format and use it everywhere: https, with or without www (pick one), and with or without a trailing slash (pick one). For example:

https://yourdomain.com/about

Every internal link, sitemap entry, and redirect should use this exact form.

Add the canonical tag to the head

Inside <head> on every page, add a link tag pointing at that page's true URL:

<link rel="canonical" href="https://yourdomain.com/about" />

The URL must be absolute, including the scheme and domain. Relative paths are ignored by some crawlers.

Make every page self-referencing

A page's canonical should point at itself, not at the homepage or a category. about points to about. Pointing many pages at one URL tells Google those pages are duplicates and drops them from results.

The exceptions are true duplicates: a print version, a ?ref= tracking variant, or a syndicated copy. Those point at the original.

Redirect the other versions

A canonical is a hint. A redirect is a rule. Set your server or host to 301-redirect http to https and www to non-www (or the reverse) so the alternate addresses do not exist as separate pages at all.

Check it in Search Console

Paste a URL into the search bar at the top of Google Search Console. The Page indexing section shows the User-declared canonical (yours) and the Google-selected canonical (what Google decided). They should match. If they do not, Google is seeing a conflict somewhere, usually a redirect or sitemap that disagrees with the tag.

One per page. If a page has two canonical tags, Google ignores both. Check for a CMS or plugin adding one you did not know about.