Free tool
Canonical tag checker
By Tiago CostaUpdated on July 01, 2026
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.
Quick guide
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.
FAQ
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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Glossary terms
301 redirectThe 301 redirect is the type of permanent redirect that sends both the visitor and the search engine from an old URL to a new address, signaling that the change is definitive. Besides keeping people from landing on a nonexistent page, it passes most of the authority accumulated by the original URL to the new one, which makes it the correct way to change address, domain or site structure without losing positions on Google.URL parametersURL parameters are snippets added to the end of an address, after a question mark, that send extra information to the server, such as product filters, internal search terms, session identifiers or campaign tags (UTMs). They are useful for tracking traffic and organizing dynamic pages, but when poorly controlled they can create duplicate content, waste the search engine's crawling and dilute the ranking signals of a page.Canonical URLA canonical URL is the preferred version of a page when several addresses hold identical or very similar content. It is signaled to the search engine by a canonical tag (rel=canonical) in the HTML or by other signals, telling it which URL should be treated as the original, the one that appears in search and concentrates the authority of the links. It is the main tool for solving duplicate content without deleting pages or harming the user experience.302 redirectA 302 redirect is an HTTP status code that tells the browser and search engines that a page has been moved temporarily to another URL. Unlike the 301, which is permanent, the 302 signals that the original address will come back, so Google keeps the old URL indexed and does not pass authority permanently to the new address. It is the detour of choice for passing situations, such as tests, maintenance and promotions.Redirect chainA redirect chain is a sequence in which one URL redirects to another, which in turn redirects to a third, and so on, before reaching the final destination. Each extra hop adds load time, spends crawl budget and dilutes the authority passed by links. Ideally any URL should redirect only once, straight to the final address, with no intermediate steps.