canonical tag checker
Is your canonical tag
saying what you mean?
Paste a page's HTML and see its canonical tag, with the problems Google documents flagged. It reads pasted HTML only and cannot know which URL Google chooses.
Free, no account, nothing leaves your browser.
How to use it
- 1Paste the page HTML
Open the page, view its source (not the inspected DOM) and paste it. Optionally add the page's URL so the tool can compare it with the canonical.
- 2Read what it found
Every rel="canonical" link is listed with where it sits (head or body) and whether it is absolute. Flags cover rules Google documents, such as head only, absolute URLs, no fragments and one clear target.
- 3Fix the source, then re-check
Change the template or SEO plugin setting, publish, then paste the new source. To see which URL Google actually chose, use the URL Inspection tool in Search Console.
Questions
Where must the canonical tag be?
Google says a rel="canonical" link element is only accepted in the head section of the HTML, so make sure at least the head is valid HTML. A broken head can push later link elements into the body, which the tool reports as "in body".
Should the canonical be absolute or relative?
Google says to use absolute URLs rather than relative ones with the rel="canonical" link element. It supports relative paths but does not recommend them, because they can cause problems later, for example if a test site is crawled.
Can I put a fragment in the canonical?
No. Google says not to specify a URL fragment as canonical, as it generally does not support URL fragments.
Do I need a self-referencing canonical?
Google recommends a self-referential rel="canonical" on the canonical page itself. When the canonical equals the URL you entered, the tool notes it as self-referential.
What if a page has two canonical tags?
Google's canonicalization documentation we read does not describe how it handles several rel="canonical" elements, so the tool just flags them: two different targets cannot both be the preferred URL. Google advises against specifying different URLs as canonical for the same page using different canonicalization techniques. Keep one.
What about noindex together with a canonical?
Google says it does not recommend noindex to prevent selection of a canonical page within a single site, because noindex blocks the page from Search completely, and that rel="canonical" annotations are the preferred solution. The tool flags the combination so you can check it is intended.
Can the tool tell me which URL Google picked?
No. Google says it may choose a different canonical than the one you designate, for reasons such as content quality or technical signals, and tells you to check the URL Inspection tool in Search Console. This tool only reads the HTML you paste: it does not fetch pages, see HTTP headers (a Link canonical header is a separate method) or run JavaScript.
Is my HTML sent anywhere?
No. It is parsed in your browser as an inert document (scripts do not run, nothing is loaded) and shown as plain text. Input is limited to 2 MB.
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