Missing canonical tag
A canonical tag tells search engines which URL is the preferred version of a page. When it is absent, engines guess — and they do not always guess right.
What it is
This check flags indexable 200 pages that ship no <link rel="canonical"> tag at all.
Why it matters for SEO
Without a canonical, parameter variants, tracking URLs, and slash/no-slash duplicates can each be indexed separately, splitting ranking signals across near-identical pages.
Example
<!-- No canonical in the <head> -->
<head>
<title>Product page</title>
</head>
How to fix
- Add a self-referencing canonical to every indexable page:
<link rel="canonical" href="https://example.com/page">. - Use absolute HTTPS URLs that match the page's own indexable address.
- Keep canonical and internal links pointing at the same URL.
- Re-crawl to confirm each page now declares a canonical.