An XML sitemap validator checks that a sitemap file is well formed and follows the basic rules search engines expect. Enter the URL of a sitemap, such as https://example.com/sitemap.xml, and this tool fetches it, parses the XML, tells you whether it is a URL sitemap or a sitemap index, counts the URLs or child sitemaps, and lists the first 20 entries.
It reports three problems: XML that doesn't parse (a broken tag, an unescaped & or text before the XML declaration), more than 50,000 URLs in one file, which is the protocol limit, and URLs that start with http:// instead of https://. If none are found, you see "Sitemap structure looks valid". The sample list lets you confirm the entries use the right domain and protocol.
Limits: the tool checks the file's structure, not each URL. It does not request the listed pages, so it won't find 404s, redirects or noindex pages inside the sitemap, and it doesn't validate lastmod dates or the XML schema. For a sitemap index it counts the child sitemaps but doesn't open them, so check each child separately. Gzipped sitemaps (.xml.gz) and files over 5 MB can't be checked.
