Free tool · Technical SEO
Sitemap validator
Enter your domain or sitemap URL, or paste the XML. The validator checks structure and limits, follows sitemap indexes, flags URLs blocked by robots.txt and spot-checks pages for errors, redirects, noindex and wrong canonicals.
What gets checked
- XML syntax with line numbers, namespace, the 50,000 URL and 50 MB limits
- Every URL: full and valid, same host, no duplicates, valid lastmod dates
- Sitemap indexes: up to 5 child sitemaps, spread across the index
- URLs blocked by robots.txt, and whether robots.txt lists the sitemap
- 20 sampled URLs: broken pages, redirects, noindex and canonicals pointing elsewhere
How it works
Three steps, no signup.
Enter a URL or paste XML
Type your domain to find the sitemap through robots.txt, enter the sitemap URL, or paste the XML.
Run the checks
The validator parses the XML and checks structure, URLs and limits.
Fix the issues
Each problem is explained in plain language so you know exactly what to change.
FAQ
Sitemap Validator questions.
What does the validator check?
That the XML is well-formed, uses the correct sitemap namespace, that every loc is a valid absolute URL, that dates are formatted correctly and that the file stays within the 50,000 URL and 50 MB limits.
What is the sitemap URL limit?
A single sitemap can hold up to 50,000 URLs and must be no larger than 50 MB uncompressed. Larger sites split URLs across multiple sitemaps and list them in a sitemap index file.
Why is my sitemap invalid?
Common causes are relative URLs instead of absolute ones, unescaped ampersands and other characters, a missing namespace, or wrongly formatted lastmod dates. The validator points to the exact issue.
Is my sitemap sent anywhere?
Pasted XML is checked in your browser and never uploaded. When you enter a URL, Lynx fetches the public sitemap and a sample of its pages on its servers and returns only the findings.
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Tools find the work. Lynx does it.
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