Canonical tag checker
Paste a page URL and see whether it has a canonical tag, if it points to itself, and if there are duplicates. Right in your browser, no sign up.
Everything about the canonical tag
The canonical tag tells Google which version of a page is the official one when similar or duplicate URLs exist. It stops duplicate content from splitting SEO strength across several addresses and concentrates authority on the right URL.
What the canonical tag is
It is a line in the page <head> shaped like <link rel="canonical" href="...">. It points to the URL that should appear in search. When a page points to itself, it is called a self-referencing canonical, the recommended setup for most pages.
Why it matters for SEO
- Avoids duplicate content: versions with and without a trailing slash, with parameters, or http/https stop competing.
- Concentrates authority: links and signals point to a single strong URL.
- Controls indexing: you state the preferred version instead of letting Google guess.
Common canonical mistakes
| Mistake | Effect |
|---|---|
| No canonical tag | Google picks the version on its own, not always the one you want |
| More than one canonical | Google tends to ignore all of them |
| Canonical to another page | Asks Google not to index this page (use on purpose) |
| Relative or broken canonical | May be ignored or point to the wrong place |
A canonical is not a redirect
The canonical is a hint for the search engine, and the page stays reachable. To actually send the user to another URL, use a 301 redirect. Use each for its own purpose.
Canonical questions
Is the checker free?
Yes, free and no sign up. Paste the URL and get the canonical analysis instantly.
What is a self-referencing canonical?
It is when a page points its canonical to its own URL. It is the recommended setup for most pages.
Can I have more than one canonical tag?
Not recommended. With more than one, Google usually ignores all of them and picks on its own.
Does a canonical remove the page from the index?
Not directly. It states the preferred version. To remove from the index, use the noindex meta tag.
Are canonical and redirect the same?
No. The canonical is a hint and the page stays reachable; a 301 sends the user and the engine to another URL.
Is my data stored?
The check runs on demand and the page content is not stored.
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