Canonical Tag Checker - Verify rel=canonical Online
Canonical Tag Checker
Verify a Page's Declared Canonical URL
Ready to Check
Enter a URL above to see its canonical tag.
Understanding the Canonical Tag
Duplicate Content
The canonical tag tells search engines which URL is the authoritative version when the same content is reachable multiple ways.
SEO Audits
Verify every page on your site correctly self-references or points to the intended canonical target.
Migration Checks
Confirm canonical tags were updated correctly after a domain migration or URL structure change.
Server-Side Fetch
Fetches are validated against SSRF protections and blocked for any private or internal address.
Why Canonical Mismatches Happen
A canonical tag pointing to a different URL than the one you requested isn't necessarily a bug — it's often intentional, telling search engines to consolidate ranking signals onto a preferred version. A mismatch is only a problem when it's unintentional, such as a staging URL accidentally left in production.
Key Takeaways
- Redirect-Aware: Follows safe redirects to the final page before checking its canonical tag.
- Absolute URL Resolution: Relative canonical hrefs are resolved to absolute URLs automatically.
- SSRF-Protected: Every fetch (including redirect hops) is validated to resolve to a public IP address only.