SEO Tools
Canonical URL Checker
Check whether a page has a canonical URL tag.
Enter a URL to check whether it has a canonical tag set.
JustChecker tracks your on-page SEO signals continuously.
Frequently Asked Questions
When the same or very similar content is reachable at multiple URLs (with/without a trailing slash, with tracking parameters, http vs https), a canonical tag tells search engines which single version should be treated as authoritative, consolidating ranking signals onto it.
Search engines will attempt to determine the canonical version on their own using various signals - this often works reasonably well, but an explicit tag removes ambiguity entirely rather than relying on automated inference.
Yes - this is valid and sometimes intentional, such as when syndicated content should have ranking credit attributed back to the original publishing site rather than the site republishing it.
A canonical tag accidentally pointing to the wrong page (often left over from copy-pasted template code) can inadvertently tell search engines to ignore the actual page in favor of an unrelated one - always verify it points to itself unless intentionally otherwise.
Yes, it's widely considered good practice - a self-referencing canonical provides an explicit, unambiguous signal even in the absence of a known duplication problem, and costs nothing to include.