Sitemap validator
Fetch your sitemap by URL or paste the XML and get every problem listed — wrong tags, malformed URLs, bad dates, size limits — plus a summary of what's inside.
Enter a bare domain and we'll try /sitemap.xml, the conventional location.
Checked against the sitemaps.org spec
The validator fetches your sitemap (or takes pasted XML), confirms it parses as XML, and then walks every entry against the sitemap protocol: root element and namespace, required loc tags, URL shape and length, the 50,000-URL limit, W3C datetime lastmod values, the changefreq enum, and the 0.0–1.0 priority range.
Problems come back as a list — errors for things that can make crawlers reject the file, warnings for spec violations they usually tolerate — each with the offending value and entry number, plus a summary of what's inside: how many URLs, and how many carry lastmod, changefreq, and priority.
What usually breaks sitemaps
- Relative or schemeless URLs in loc — every loc must be absolute, starting with http:// or https://
- Unescaped ampersands in URLs — & must be written as & inside XML
- lastmod in a local date format instead of W3C datetime (YYYY-MM-DD)
- A missing or wrong xmlns namespace on the urlset element
- One giant file past the 50,000-URL limit instead of a sitemap index pointing at parts
Frequently asked questions
What does the validator check?
Everything the sitemaps.org spec asks for: the root element and its namespace, that every url entry has a loc, that each loc is an absolute HTTP(S) URL of at most 2,048 characters, that the file stays under 50,000 URLs, that lastmod values are valid W3C datetimes, that changefreq uses the allowed values, that priority is a number between 0.0 and 1.0, and it flags unknown tags inside url entries.
Does it handle sitemap index files?
Yes. If the root element is sitemapindex, it validates each child sitemap entry and lists them, with a button to run the validator on any child sitemap directly.
Can I just enter my domain?
Yes — enter example.com and the validator tries example.com/sitemap.xml, the conventional location. If your sitemap lives elsewhere (check your robots.txt for a Sitemap: line), paste its full URL.
What is a valid lastmod date?
The W3C datetime format: a plain date like 2026-08-28, or a full timestamp like 2026-08-28T09:30:00Z or 2026-08-28T09:30:00+02:00. Anything else — like 08/28/2026 or a bare month — is flagged.
Do changefreq and priority still matter?
Google has said it ignores both, but other consumers may not, and invalid values are still spec violations worth fixing. The loc and lastmod are the fields search engines actually use — keep lastmod accurate.
My sitemap is huge — will it validate all of it?
Fetched sitemaps are capped at 2 MB; if yours is bigger, the validator says so and counts are marked partial. The spec caps a single sitemap at 50,000 URLs and 50 MB uncompressed anyway — past that you should split it and list the parts in a sitemap index.
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