Guide
Canonical guide
What Is a Canonical Tag?
The rel=canonical link element explained: what it is, what it does, and how Google uses it.
Learn it properly
Canonical tag guides
In-depth, plain-English guides to the canonical tag and URL canonicalization.
These guides cover the concepts behind every fix on this site: what the canonical tag is, what a canonical URL means, how canonicalization works, the exact rel=canonical syntax, and how the canonical tag relates to redirects and hreflang. Read them once and the Search Console statuses and platform settings stop being mysterious.
Guide
Canonical guide
What Is a Canonical URL?
The preferred URL Google indexes for a set of duplicates, and how it is chosen.
Guide
Canonical guide
What Does 'Canonicalized' Mean?
A plain-English definition of canonicalization and what 'canonicalized' means.
Guide
Canonical guide
Canonicalization in SEO
How search engines consolidate duplicate URLs, and every signal that influences the choice.
Guide
Canonical guide
Duplicate Content and Canonical Tags
How duplicate content happens and how the canonical tag consolidates it.
Guide
Canonical guide
How to Add a Canonical Tag in HTML
Copy-paste examples for the HTML head, the HTTP header, and non-HTML files.
Guide
Canonical guide
rel=canonical Syntax Reference
The exact syntax, attributes, placement rules, and what Google ignores.
Guide
Canonical guide
Canonical Tag vs 301 Redirect
When to consolidate with a canonical and when to move a URL with a redirect.
Guide
Canonical guide
Canonical Tags vs Hreflang
Why every hreflang page must self-canonicalize, and how the two work together.
Guide
Canonical guide
Canonical Tag Best Practices
A practical checklist for implementing canonicals correctly across a site.
Guide
Canonical guide
Common Canonical Tag Mistakes
The canonical errors that quietly cost rankings, and how to avoid each one.