Tools

Canonical Checker

Make sure your page points to the right canonical URL.

URL to check

Couldn't fetch that page. Make sure the URL is correct and publicly accessible.

Why does the canonical tag matter for duplicate content?

When the same content can be reached through multiple URLs (tracking parameters, http vs https, www vs non-www), Google can get confused about which URL is the "real" one. A canonical tag gives it a clear instruction: this is the official version, index this one. Without it, your page risks competing against itself in search results.

Frequently asked

Questions about the Canonical Checker

What happens if a page has no canonical tag?

Google will try to guess which version is the "master" one on its own — and sometimes it guesses wrong, which can hurt the page you actually wanted prioritized.

Can a canonical point to a different domain?

Yes, that's called a cross-domain canonical — commonly used when the same content is republished on another platform (like Medium) and you want Google to keep indexing the version on your own site.

Is a self-referencing canonical (pointing to itself) necessary?

Strongly recommended, even for a page with only one URL — it's standard defensive practice against unexpected URL duplication (e.g. from UTM parameters).

Does canonical directly affect ranking?

Not ranking directly, but it prevents "signal splitting" — without a correct canonical, SEO signals (links, engagement) can get scattered across multiple URLs instead of consolidating on one main page.