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Canonical Tag Checker
Inspect canonical tags in pasted HTML for duplicates, relative URLs and page mismatches.
Free
No sign-up
Runs in your browser
What is Canonical Tag Checker?
Canonical Tag Checker is a free online seo tool from GigaTools. Inspect canonical tags in pasted HTML for duplicates, relative URLs and page mismatches. It runs entirely in your web browser, so nothing is uploaded and it works on any device without installing software.
Common uses
- Inspect canonical tags before a release.
- Find conflicting canonical declarations in HTML.
How it works
How to use Canonical Tag Checker
Review the findings
Inspect missing or multiple canonical tags, absolute URLs and mismatches.
Check the live destination
Verify redirects, HTTP headers and indexing separately.
FAQ
Good to know
How do I use Canonical Tag Checker?
1. Paste page HTML: Paste source or rendered HTML. Enter the page URL for comparison. 2. Review the findings: Inspect missing or multiple canonical tags, absolute URLs and mismatches. 3. Check the live destination: Verify redirects, HTTP headers and indexing separately.
Does this fetch the page?
No. Only pasted HTML is checked. HTTP Link headers and the canonical selected by Google are outside this check.
Is a different canonical always wrong?
No. A duplicate page may point to an equivalent preferred page. Verify that the choice is intentional.
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