Sitemap Validator — Free Online XML Sitemap Linter
Catch every common sitemap error in seconds. Validates against the sitemaps.org schema and flags problems with severity. Upload a file or paste a URL.
About this sitemap validator
This is a free online tool that validates any XML sitemap against the sitemaps.org 0.9 specification. It flags every common sitemap mistake — missing tags, invalid values, malformed dates, oversize files — and tells you exactly which entries are problematic. No signup, no watermark, no daily quota beyond a small per-IP rate limit.
What this validator catches
- Empty or missing
<loc>tags inside<url>elements - Invalid
<changefreq>values (must be one of always, hourly, daily, weekly, monthly, yearly, never) - Invalid
<priority>(must be a decimal between 0.0 and 1.0) - Malformed
<lastmod>dates that do not match the W3C Datetime format - URLs using
http://instead ofhttps://(warning — search engines prefer https) - Files exceeding the 50,000-URL limit per file (must be split into multiple sitemaps with a sitemapindex)
- Empty
<sitemapindex>documents with no children - XML well-formedness errors
- DTD or entity declarations (rejected outright as a security measure against billion-laughs and XXE attacks)
Two ways to validate
Upload an XML file: drag-drop or click to upload your sitemap.xml or sitemap.xml.gz. Up to 25 MB. Your file is parsed in memory and discarded immediately.
Validate by URL: paste the URL of a publicly accessible sitemap. We fetch it (gzip auto-handled) and run the same checks.
How to fix common errors
Most failures fall into three buckets. Empty <loc> errors come from CMS plugins that emit placeholder rows for unpublished content; the fix is in your CMS settings. Invalid <changefreq> or <priority> values usually come from custom sitemap templates with hardcoded strings; replace with valid values. Malformed <lastmod> dates come from custom templates writing locale-formatted strings; switch to ISO 8601 (YYYY-MM-DD or YYYY-MM-DDThh:mm:ssZ).
Privacy
We do not log the contents of files you upload or URLs you submit. Aggregate counters (validations per day) are recorded for capacity planning. Files and fetched documents live in memory only.
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Frequently asked questions
How do I validate a sitemap?
Either upload your sitemap.xml file or paste the URL of a publicly accessible sitemap. We check it against the sitemaps.org schema, flag every issue we find, and tell you whether the file is valid.
What does this validator catch?
Missing or empty <loc> tags, invalid <changefreq> values, out-of-range <priority>, malformed <lastmod>, http:// URLs that should be https, the 50,000-URL-per-file limit, and structural issues like a <sitemapindex> with no children.
Is the tool free?
Yes, no signup, no watermark. Files up to 25 MB are accepted; for larger sitemaps split them first.
Does it support sitemap-index files?
Yes. The validator detects whether the document is a urlset or a sitemapindex and applies the appropriate schema rules.
Where is my sitemap stored?
It is parsed in memory and discarded immediately. We do not log, save, or share contents.