RoborankCanonical URL Checker
Enter a URL and see which page it tells search engines to index, how many redirects it goes through first, and whether anything on the page contradicts it.
What this page says
Redirect chain
Every hop between the URL you entered and the page that finally answered.
Findings
Free, no signup. We fetch the page the way a browser would and read what is in the HTML.
One page at a time is slow.
Roborank crawls the whole site, finds the canonical, redirect and indexing problems across every page, and fixes them in your CMS.
See how Roborank worksWhat a canonical tag is for
Most pages are reachable at more than one address. With and without a trailing slash, with and without www, over http and https, with a tracking parameter on the end, through a print view, as an AMP copy. To a search engine those are separate URLs with the same content, and it has to pick one to rank.
The canonical tag is how you make that choice instead of leaving it to Google. It is a hint rather than a directive, so it can be overruled, but a clear and consistent canonical is followed most of the time. An unclear one is what causes the two problems everyone recognises: the wrong version of a page ranking, and traffic split across duplicates so neither one ranks well.
What this checker looks at
- Every
rel="canonical"on the page, in source order. More than one is a bug, because Google discards all of them when they conflict. - The full redirect chain from the URL you entered to the page that finally answers, with the status code at each hop.
- Whether the canonical points at itself, at another page, or at an http URL from an https page.
- The meta robots tag and the X-Robots-Tag header, because a noindex on the page cancels out whatever the canonical says.
- og:url, which is a different field with a different job, and which quietly disagreeing with your canonical will skew your analytics.
The four canonical problems worth fixing
Two canonical tags
Usually the theme adds one and the SEO plugin adds another. Google sees the conflict and ignores both, which puts you back to it choosing for you.
Canonical pointing at the homepage
A template bug that hardcodes the site root on every page. The effect is that the entire site tells Google only the homepage is worth indexing.
Canonical plus noindex
These two directives contradict each other. The page says do not index me, and also index that other page instead of me. Google's guidance is to never combine them.
Canonical with tracking parameters
If the canonical carries a utm or a session id, every visit from a campaign creates a new canonical. The clean URL is the only one that belongs in the tag.
When a canonical should point somewhere else
A self-referencing canonical is right for a normal indexable page. Pointing elsewhere is correct in specific cases: a paginated series where every page names page one, product variants that share a description, syndicated copies of an article that name the original, and printer-friendly or AMP versions that name the main page.
It is a mistake everywhere else. If a page has content worth ranking for and it tells Google to index a different page, that content will not rank, and the usual way this happens is a template applying one rule to pages it was never meant to cover.
Redirects and canonicals together
A redirect is stronger than a canonical. If the URL you entered 301s somewhere, the canonical on the destination is the one that counts, and the tool shows you the chain so you can see what happened. Chains of more than two hops are worth flattening: they slow down crawling, they leak a little signal at each hop, and they tend to grow over time as one redirect gets added on top of another.
Frequently asked questions
What is a canonical URL?
The version of a page you want search engines to index when the same content is reachable at several addresses. You declare it with a rel="canonical" link tag in the page head.
Should every page have a self-referencing canonical?
For a normal indexable page, yes. It costs nothing and it removes any ambiguity when the page is reachable with a trailing slash, a parameter or a different case. Point it elsewhere only when the page really is a duplicate or a variant of another one.
Is a canonical tag a directive or a hint?
A hint. Google considers it alongside other signals like internal links, sitemaps and redirects, and it can choose a different URL when those disagree. Consistent signals are what make it stick.
Can I have two canonical tags on one page?
You can, but you should not. When Google finds conflicting canonicals it ignores all of them and picks a URL itself. This checker flags it because the usual cause is a theme and an SEO plugin both adding one.
Can a canonical point to a page that redirects?
Technically yes, and it is a mistake. The canonical should be the final URL that returns 200. Pointing it at a redirect makes the signal ambiguous and wastes crawl budget.
Should I use noindex and canonical together?
No. Google specifically advises against it, because the two directives say different things. Use noindex to keep a page out of the index, or a canonical to consolidate it into another page, not both.
Does the canonical need to be an absolute URL?
Relative URLs are technically valid and resolve against the page, but absolute URLs are far safer. A relative canonical on a page served at two paths resolves to two different canonicals.
Is this canonical checker free?
Yes, with no signup. There is a daily limit per visitor so the tool stays available to everyone.