What is a canonical tag?

It is a link in the head that names the preferred address for a page. Search engines use it to pick one URL when the same content is reachable at several.

Should a page point its canonical at itself?

Usually yes. A self-referencing canonical is the safe default. Point elsewhere only when the page really is a copy of another.

Is the canonical a command?

No. It is a strong hint. Search engines can pick a different URL if other signals disagree.

Why does findable skip canonical_self?

It needs a canonical to compare against. With no canonical tag, canonical_self and canonical_absolute are skipped and canonical fails.

Canonical tags and duplicate content: how to get them right

By findable team. Published 2026-10-15. Updated 2026-10-15.

Contents

Which checks cover canonical?
What does the tag look like?
When should the canonical point elsewhere?
What are the common mistakes?
How do you reduce duplicate content in the first place?
Key takeaways

The same page is often reachable at many addresses. With and without www, with tracking parameters, with a trailing slash, over http and https. To a crawler these can be separate pages with identical content. A canonical tag says which one counts.

Which checks cover canonical?

Check id	What it tests	Passes when
`canonical`	A canonical link is present	The tag exists
`canonical_self`	The canonical points to this page	The canonical resolves to the scanned URL
`canonical_absolute`	The canonical is an absolute URL	It starts with a scheme like `https:`
`og_url_matches_canonical`	`og:url` agrees with the canonical	Both name the same page
`meta_robots_conflict`	Robots directives do not contradict	No `index` with `noindex`

What does the tag look like?

<link rel="canonical" href="https://example.com/care">

Use the full URL, with the scheme and host. A relative value like /care is easy to break and fails canonical_absolute.

When should the canonical point elsewhere?

When the page is a deliberate copy: a print version, a filtered list, or a tracking-parameter variant. Then canonical_self will fail, and that is correct. Decide on purpose. If a page is meant to rank by itself, it should point to itself.

What are the common mistakes?

Canonical pointing at the home page from every page.
A canonical that differs from the redirect target or from og:url.
Two canonical tags that disagree.
A canonical pointing at a URL that is blocked or marked noindex. See robots.txt and AI crawlers.
Mixing index and noindex in one robots meta.

How do you reduce duplicate content in the first place?

Redirect http to https and pick one hostname.
Pick a trailing slash policy and keep it.
Keep parameters out of internal links.
Give each page its own title and description. See meta descriptions.

Key takeaways

One absolute canonical per page, normally pointing at itself.
Point it elsewhere only for true copies.
Keep og:url equal to the canonical.
More SEO ids are in every SEO check.

FAQ

What is a canonical tag?: It is a link in the head that names the preferred address for a page. Search engines use it to pick one URL when the same content is reachable at several.
Should a page point its canonical at itself?: Usually yes. A self-referencing canonical is the safe default. Point elsewhere only when the page really is a copy of another.
Is the canonical a command?: No. It is a strong hint. Search engines can pick a different URL if other signals disagree.
Why does findable skip canonical_self?: It needs a canonical to compare against. With no canonical tag, canonical_self and canonical_absolute are skipped and canonical fails.

How does findable score a page?

Family	Weight	Question it asks
SEO	50%	Can crawlers read and index this page?
AEO	25%	Is it easy to lift an answer from this page?
GEO	25%	Does the page give a generative model a reason to cite it?

The hosted audit waits up to 10 s for a page and fetches at most 5 MB. It reads robots.txt and llms.txt up to 512 KB each.

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