Free Tools/Canonical Tag Checker

Free Tool · No signup

Canonical Tag Checker

Check any page's canonical tag: whether it exists, whether it's absolute, and whether it actually points where you think it does. A wrong canonical can quietly send Google to index the wrong URL.

Why use our Canonical Tag Checker

Catches the mistake that hides in plain sight

A canonical pointing to the wrong URL looks completely normal in the page source, this flags it explicitly instead of relying on a manual view-source check.

Checks for duplicate canonical tags

More than one canonical tag on a page leaves search engines to pick one unpredictably, this catches that too.

Instant, no crawl needed

Paste a URL and get a full check in seconds.

Free, no signup

Check any page instantly, no account required.

Page URL *

Real Canonical Tag Checker example: before vs. after

A page copied from a staging template that still carried the staging domain's canonical tag.

Before · Before

2/4

Checks passing

The canonical tag pointed to the staging environment, telling Google to index that instead of the live page.

After · After the fix

4/4

Checks passing

Canonical correctly self-references the live production URL.

Frequently Asked Questions

Do I need a canonical tag on every page?

It's a strong best practice even when a page isn't a duplicate, a self-referencing canonical removes ambiguity about which version of a URL (with or without parameters, trailing slash) Google should treat as authoritative.

When should a canonical NOT point to itself?

When the page is a genuine duplicate or near-duplicate of another page, print versions, tracking-parameter URLs, or paginated variants pointing back to the main page are common legitimate cases.

What happens if I have two canonical tags?

Search engines have to guess which one to trust, and different engines may pick differently. Fix this by making sure your CMS or template only outputs one.

Can a relative canonical URL cause problems?

It can be resolved incorrectly in some edge cases, using an absolute URL removes any ambiguity and is what search engines explicitly recommend.

Check your whole site's technical SEO

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