Canonical URL Checker
Paste HTML source to analyze canonical tags, og:url, and base href. Detect duplicates, protocol mismatches, placement issues, and get SEO recommendations.
HTML Source Input
Check Summary
Paste HTML source code to run canonical checks.
Canonical Tag Best Practices
Each page should have exactly one <link rel="canonical"> tag in the <head>. Multiple canonicals confuse search engines.
Always use the full URL (https://example.com/page) rather than a relative path (/page). Google strongly recommends absolute URLs.
Every page should include a self-referencing canonical tag pointing to itself, even if no duplicates exist. This prevents issues with URL parameters.
The Open Graph og:url meta tag should match the canonical URL for consistency between search engines and social platforms.
If your site uses HTTPS, the canonical URL must also use HTTPS. Never mix protocols.
Pick one format (with or without trailing slash) and use it consistently. Set up redirects for the other version.
The canonical tag must be in the <head> section. Search engines may ignore canonical tags found in the <body>.
The canonical URL should return an HTTP 200 status. Pointing a canonical to a redirect, 404, or 5xx URL causes issues.
Frequently Asked Questions
What is a canonical tag?
A <link rel="canonical"> tells search engines which URL is the preferred version of a page, consolidating ranking signals and avoiding duplicate content.
Should og:url match canonical?
Yes. For consistency between search engines and social platforms, og:url should match the canonical URL.
Why absolute URLs?
Google recommends absolute URLs in canonical tags. Relative paths may be misinterpreted across different hostnames or protocols.
Is the Canonical URL Checker free to use?
Yes, the Canonical URL Checker is 100% free with no registration, no hidden fees, and no usage limits. All processing happens locally in your browser, ensuring complete privacy.
Is my data safe with this tool?
Absolutely. The Canonical URL Checker processes everything client-side in your browser. No data is uploaded to or stored on any server. Your content remains private on your device at all times.
Does the Canonical URL Checker work on mobile devices?
Yes, the Canonical URL Checker is fully responsive and works on smartphones and tablets. You can use it on any device with a modern web browser -- no app download required.
Do I need to create an account to use this tool?
No account or registration is needed. Simply open the Canonical URL Checker in your browser and start using it immediately. There are no sign-up walls or usage restrictions.
Does this tool follow Google's latest guidelines?
Yes, the Canonical URL Checker is built following current Google Search guidelines and best practices. We regularly update the tool to reflect changes in search engine requirements.
How do I use the Canonical URL Checker?
Simply enter your input in the provided field, adjust any settings to your preference, and the tool will process it instantly. You can then copy the result to your clipboard or download it.
Which browsers are supported?
The Canonical URL Checker works in all modern browsers including Chrome, Firefox, Safari, Edge, and Opera. For the best experience, use the latest version of your preferred browser.
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About Canonical URL Checker
Canonical URL Checker is a free, browser-based tool in our SEO Tools collection. Everything runs locally on your device — no uploads, no sign-up, and your data stays private.