Sitemap Validator
Check your XML sitemap against the sitemap protocol. Paste the XML for an instant answer, or enter the sitemap URL and we will fetch it — errors and warnings come back with line numbers.
XML sitemap checker
Validate your XML sitemap properly
What this sitemap validator checks
Paste your XML or enter a sitemap URL and this validator tests it against the sitemaps.org protocol — the specification Google, Bing and every other crawler reads. It confirms the XML is well-formed, the <urlset> carries the correct namespace, every entry has an absolute <loc>, <lastmod> dates use the W3C datetime format, and the file stays under the protocol’s hard limits of 50,000 URLs and 50MB uncompressed. Problems come back on two lists: errors that stop crawlers using the file, and warnings they tolerate but you should still fix — each with a line number so you can go straight to it.
Why a valid sitemap matters
A sitemap is how you tell search engines — and increasingly AI crawlers — what your site contains and when it changed. A broken one fails silently: Search Console might show “couldn’t fetch” or simply index less of your site, and you rarely get told why. The most expensive failures are the quiet ones, like a namespace typo that makes every crawler discard the file while it still looks fine in a browser.
How to fix the most common errors
Missing or wrong namespace — the opening tag must read <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"> exactly. Most generators get this right; hand-edited files often don’t.
Relative URLs — every <loc> needs the full absolute address including https://. Crawlers won’t guess your domain.
Invalid lastmod dates — use 2026-08-15 or the full 2026-08-15T14:30:00+00:00 form. Formats like 15/08/2026 are ignored, which throws away the freshness signal.
Too many URLs — past 50,000 entries, split into multiple sitemaps referenced by a sitemap index file. Most CMS plugins do this automatically once enabled.
Mixed domains — entries pointing at other hostnames (including www vs non-www) are only accepted when every domain is verified in the same Search Console account. Keep one sitemap per host unless you know you need cross-submission.
More free tools
- Site Answerability Check See which visitor questions your website can answer.
- Sitemap Extractor Pull every URL out of any sitemap.
- Sitemap Checker Find every sitemap a site exposes and whether they validate.
- Robots.txt Checker See which AI crawlers can access your site.
- LLMS.txt Checker Check your llms.txt follows the standard, with AI suggestions.
- LLMS.txt Generator Generate an llms.txt file from your sitemap.
Related guides
Fixing what the validator found
Errors above, and not sure what they mean? Start here.
- How to check a sitemap — what each error means and how to fix it
- Sitemap for WordPress — the problems specific to WordPress, including caching and permalinks
- How to find the sitemap of a website — if the file was not where you expected
- Answerability check — once the sitemap is clean, see what an AI can actually answer