Canonical URL Checker & Duplicate Content Audit
Verify `` tags, check self-referential integrity, and resolve duplicate content issues for search engine indexing.
How to Use Canonical URL Checker
Input URL or Markup
Enter the target webpage URL, domain name, or paste the raw markup into the input field.
Run Technical Audit
Click the action button to parse tags, simulate crawler directives, or query live DNS records.
Review Actionable Insights
Inspect diagnostic status badges, recommendations, and copy formatted audit results.
Frequently Asked Questions
Why is rel=canonical necessary?
Canonical tags tell search engine spiders which URL represents the master copy of a page, preventing duplicate content penalties caused by query parameters or tracking codes.
100% In-Browser & Free
All technical SEO audits, crawler checks, and syntax parsing execute privately inside your browser without storing your confidential URLs or site data.
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