Canonical Tag Checker
Verify a page's canonical tag and catch duplicate-content mistakes.
This check runs through this site's own server, so it works for any public URL — no CORS or browser restrictions.
How to use the Canonical Tag Checker
- 1 Enter the page URL and click Check canonical.
- 2 See whether a canonical tag is declared and whether it is an absolute URL.
- 3 Compare the canonical against the final URL to see if it is self-referencing or points elsewhere.
Frequently asked questions
What is a canonical tag for?
A <link rel="canonical"> tag tells search engines which URL is the "master" version when the same or similar content is reachable at more than one URL (e.g. with tracking parameters, http vs https, or a print view), consolidating ranking signals onto one page.
What does "self-referencing canonical" mean?
It means the page points its canonical tag at its own URL. This is the most common and safest setup — it explicitly confirms this exact URL is the preferred version of itself.
Is it a problem if my canonical points to a different URL?
Not necessarily — pointing a duplicate or parameterized URL at the "real" page is intentional and useful. It is only a problem if an important, unique page accidentally canonicalizes to a different URL, which tells search engines to effectively ignore it.
Should the canonical URL be absolute or can it be relative?
Use an absolute URL (with https:// and the full host). Google explicitly recommends absolute canonicals, since a relative one can be resolved incorrectly depending on the page's <base> tag or how it was crawled.
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