Canonical Checker

Common canonical mistakes

The target should be an absolute URL that returns 200 and is indexable: a canonical pointing to a redirect, a 404, or a page with noindex sends conflicting signals and is often ignored. A template that sets every page's canonical to the home page, or leaves a staging domain in it, is a frequent cause of pages dropping out of search.

Tracking parameters make a page an alternate of itself here: ?utm_source=news in the checked URL does not match a canonical without it. That is expected and correct.

Signals that must agree

Search engines treat the canonical as a strong hint and weigh it against other signals: which URL internal links use, which is in the sitemap, and where redirects point. When internal links point to /shoes?color=red while the canonical says /shoes, the hint may be overruled.

Files such as PDFs can declare a canonical in an HTTP Link header instead; this tool reads only the HTML element. For the full picture, check noindex and the sitemap as well.

How to use it

1. Enter the exact page URL you want to inspect.
2. Choose Check canonical.
3. Review whether the signal is missing, self-referencing, or points elsewhere.

Privacy & limitations

The public page is checked through TOEA’s API and the URL is not stored. This reads one HTML signal and does not determine how a search engine ultimately canonicalizes a page.