Canonical URL Checker
Verify that canonical tags are correctly configured on any webpage.
What This Tool Checks
Comprehensive canonical tag analysis for SEO best practices.
Canonical Detection
Finds canonical tags in HTML and HTTP Link headers, detecting missing or duplicate declarations.
Self-Referencing Check
Verifies whether the canonical URL points back to the current page, a key SEO best practice.
Protocol Validation
Detects HTTP vs HTTPS mismatches between the page URL and its canonical tag.
WWW Consistency
Checks that www and non-www versions are consistent between the page and canonical URL.
How It Works
Three simple steps to validate your canonical tags.
Enter a URL
Paste any webpage URL. The tool fetches the page and inspects its HTML and HTTP headers.
Analyze Canonical Tags
The tool extracts canonical link tags, checks for duplicates, and compares against the actual URL.
Review Results
See the canonical URL found, comparison with the actual URL, and a list of any issues detected.
Frequently Asked Questions
Common questions about canonical URLs and SEO.
What is a canonical URL?
A canonical URL is the preferred version of a webpage that you want search engines to index. It is specified using a <link rel="canonical"> tag in the HTML head. When multiple URLs serve similar or identical content, the canonical tag tells search engines which version to treat as the original.
Why is a self-referencing canonical important?
A self-referencing canonical is when a page's canonical tag points to its own URL. This is considered a best practice because it explicitly tells search engines that this page is the preferred version of itself, preventing issues with URL parameters, tracking codes, or other variations that could create duplicate content.
What happens if I have multiple canonical tags on a page?
Having multiple canonical tags on a single page is an error. Search engines may ignore all canonical signals when they encounter conflicting declarations, or they may pick one arbitrarily. Always ensure each page has exactly one canonical tag.
Should my canonical URL use HTTP or HTTPS?
Your canonical URL should always use HTTPS if your site supports it. Using an HTTP canonical on an HTTPS page creates a protocol mismatch that can confuse search engines. Consistent protocol usage in canonical tags helps consolidate link equity on your preferred secure version.
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