About this tool
Review the static relationship between two authored URLs without treating syntax checks as live response, content, indexability, or Google-selection evidence.
Canonical URL Checker compares one current page URL with one intended canonical target entirely in the browser. It validates bounded absolute HTTP(S) syntax, exposes normalized origin, path, and query relationships, and generates an escaped link element without fetching either address.
- Rejects non-HTTP(S), relative, credentialed, fragmented, whitespace-containing, and oversized URLs before generating output.
- Separates hostname, origin, protocol, path, case, trailing slash, query count, duplicate key, and known tracking-key evidence.
- Escapes the normalized canonical href for an HTML link element while preserving warnings that still require content and deployment review.
How to use Canonical Checker
Enter the exact current page and canonical target URLs, resolve input errors, then review protocol, hostname, origin, path, case, slash, and query findings. Copy the tag only after confirming that the pages are duplicate or very similar and the target is the deployed representative URL.
When this tool is useful
- Review canonical logic before launching templates that generate many URL variants.
- Check whether campaign parameters or filtered URLs should collapse to a cleaner preferred URL.
- QA a CMS update when canonicals suddenly point off-domain or keep extra parameters.
Practical tips
- Use an absolute URL and do not include a fragment in the canonical target.
- Keep internal links and sitemap signals consistent with the intended representative URL.
- Inspect the deployed target before assuming it is successful, indexable, non-redirecting, or content-equivalent.
Examples you can test
Load an example, compare the result with the expected output, then replace it with your own input.
Check a page canonical
Example input
Page: https://example.com/blog/post, canonical: same URL
Expected output
Exact self-reference with normalized URL evidence
The comparison proves authored syntax and equality, not the live response or Google-selected canonical.
Detect tracking parameters
Example input
Page URL with UTM keys, canonical target without them
Expected output
Same-path query-variant relationship and escaped tag
Tracking detection is based on parameter keys; other query parameters may represent unique content and require review.
Validation checklist
- Confirm both authored URLs are absolute HTTP(S) addresses without credentials or fragments.
- Review origin, path, case, slash, and query differences against actual content equivalence.
- Inspect the deployed target status, redirects, robots, internal links, sitemap signals, and selected canonical separately.