What is canonical URL?

The plain definition

A canonical URL is the address you name as the “main” version of a page. The same content can often be reached at several addresses: with and without www, with a tracking code on the end, or through a filter. A canonical tag in the page’s code tells search engines which one to treat as the original, so signals are not split between copies.

An example

Your service page loads at example.com/drain-cleaning and also at example.com/drain-cleaning?utm_source=email. Both show the same text. A canonical tag on both pointing to the clean address tells Google to list only that one and to count visits and links toward it.

Why it matters for a local business

Most small sites never need to think about this, but problems appear after a redesign, a move to https, or when a tool adds extra address parts. If the wrong version ends up listed, the page can look duplicated or lose strength. A quick check of your redirects usually shows what is happening.

Check it for free

See where you stand with the free redirect checker. If you would rather have it handled, our Websites service covers this as part of the monthly work.

Related terms

• Duplicate content
• Redirect
• Indexing

Part of the SEO glossary. New to all this? Start with the beginner’s SEO guide.