Page has a canonical link

canonical_exists

Checks if the page has a rel=canonical link tag.

What does this rule check?

The canonical tag tells search engines which version of a URL is the preferred one. This prevents duplicate content issues when the same content is accessible via multiple URLs (with/without www, trailing slashes, query parameters, etc.).

Why is this important?

Without canonical tags, search engines may index duplicate versions of the page, diluting ranking signals across multiple URLs. This can significantly harm your search visibility.

How to fix

Add a canonical link tag pointing to the preferred URL for the page.

Examples

<head>
  <title>My Page</title>
  <!-- No canonical tag -->
</head>

<head>
  <title>My Page</title>
  <link rel="canonical" href="https://example.com/my-page" />
</head>

Agent fix snippet

Copy this snippet and paste it into your AI coding agent to fix this issue automatically.

Add a canonical tag in <head>:

<link rel="canonical" href="https://example.com/current-page-url" />

Use the full absolute URL. It should point to the preferred version of the page.