Canonical Tag Checker
Check the canonical tags of your web pages. Verify self-referencing, absolute URLs, consistency with og:url and detect duplicate content issues.
Why is the canonical tag important for SEO?
What is a Canonical Tag?
The canonical tag (also known as rel="canonical") is an HTML element that tells search engines which version of a web page should be considered the original. When the same content is accessible from multiple different URLs — due to tracking parameters, www/non-www variations, http/https protocol or trailing slashes — the canonical tag resolves the ambiguity by indicating to Google the preferred version.
Without a correct canonical tag, Google may consider the variants as duplicate pages, diluting link equity across multiple URLs and penalizing organic rankings. The tag is placed in the <head> of the HTML document with the format: <link rel="canonical" href="https://example.com/page">
A canonical tag checker analyzes the canonical configuration on your page, verifying it is present, uses an absolute URL, is self-referencing (when appropriate) and is consistent with other signals like og:url and the HTTP Link header.
Why the Canonical Tag is important for SEO
A correctly configured canonical tag brings concrete benefits for indexing and ranking.
Prevents duplicate penalties
Google may penalize pages with duplicate content. The canonical clarifies which URL is the original, protecting your ranking.
Consolidates link equity
Without a canonical, backlinks are distributed across multiple URLs. With a canonical, all value is concentrated on the preferred page.
Optimizes crawl budget
Googlebot has limited resources to crawl your site. The canonical reduces duplicate pages to crawl, improving efficiency.
Controls indexing
You decide which version of the page appears in search results, preventing Google from choosing the wrong version.
Manages parameters and variants
UTM parameters, filters, sorting and pagination create different URLs for the same content. The canonical unifies everything.
Improves SEO performance
A site with correct canonicals is cleaner in Google's eyes, with stronger and more consistent ranking signals.
How our Canonical Tag Checker works
Three steps to check your page's canonical configuration, no registration required.
Enter the page URL to check
Type or paste the full web page address in the field above. The tool accepts any publicly accessible URL.
The tool analyzes the canonical tag and related signals
The tool fetches the page's HTML and HTTP headers, extracting the canonical tag, og:url and any Link rel=canonical header for a complete analysis.
Get score, URL comparison and suggestions
Get a score from 0 to 100, a visual URL comparison, the result of each check and practical suggestions to fix any issues.
Frequently asked questions about Canonical Tags
Everything you need to know about the canonical tag and duplicate content management.
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