Page canonicalised to another URL
What it is
The page’s canonical tag, <link rel="canonical">, points to a different URL. The tag names the main version when several URLs show the same content, so pointing elsewhere says: this page is a copy, show that one in search instead.
Why it matters
That is right for true copies, such as a product reached through two category paths or a URL with tracking parameters. It is a problem when the page has its own content. Google treats the canonical as a strong hint : it usually leaves this page out of results and credits the other URL, and AI assistants that rely on a search index are then likely to see only that URL. A template that stamps one canonical onto many pages, or page 2 of an archive canonicalised to page 1, can hide whole sections this way.
How Asky checks it
Asky reads the first <link rel="canonical"> with a non-empty href in the page’s raw HTML and resolves it, whether absolute or relative, against the URL the page was served from. The page is reported when the canonical names neither that URL nor, after a redirect, the URL listed for the page: a different host (www.example.com and example.com differ) or a different path, ignoring a trailing slash and the case of percent-escapes. Naming the URL that redirected here raises canonical points to a redirecting URL instead. The protocol, query string and fragment are not compared, and a canonical sent in an HTTP Link header is not read.
Reported as a warning with medium severity.
How to fix it
- Decide whether this page is a copy of the canonical URL or a page in its own right.
- If it is a copy, the canonical is doing its job: mark the issue resolved.
- If it has its own content, point the canonical at the page itself, with the correct protocol and host.
- If many pages point to one URL, fix the template or SEO plugin setting that fills in the canonical, not each page by hand.
- Check that the URL you point to answers 200 and is not redirected or blocked.
- Point your internal links at the canonical URL, so the page you want indexed is the one your site links to.
Example
https://example.com/blog/pricing-guide has its own article, but its canonical points to the blog index:
<!-- Before -->
<link rel="canonical" href="https://example.com/blog">
<!-- After: the page names itself -->
<link rel="canonical" href="https://example.com/blog/pricing-guide">