Sitemap checker and XML sitemap validator

Whether the file is reachable at a path a crawler would try, whether it parses as XML, whether robots.txt points at it, how many URLs it really submits, whether any of those URLs sit on a different host, and whether lastmod dates exist. It follows a sitemap index one level down and reads the first few children.

Because it is how most crawlers find the file. /sitemap.xml is a convention, not a rule, and a crawler that does not guess the path has no other way of knowing the file exists. A perfectly good sitemap nobody points at is an easy thing to miss, and the fix is one line.

Indirectly and modestly. Answer engines mostly retrieve through search indexes rather than crawling your sitemap directly, so a sitemap is not what gets you cited. What it does is make sure your pages are in the index that gets searched in the first place. Necessary plumbing, not a growth lever, and anyone selling it as the latter is selling something.

Yes, on purpose. This is a free tool fetching a stranger’s server, so it opens at most five children of an index. That is enough to confirm the index resolves to real URL sets. The count it reports covers only what it read, and it says so in the result rather than implying it counted everything.

A sitemap may only list URLs on the same host it is served from. Crawlers discard cross-host entries outright, so if your sitemap at example.com lists www.example.com URLs, or vice versa, those pages are not being submitted at all. This one bites sites that changed canonical hosts and left the generator configured for the old one.

Each run is logged with the URL, a summary of what we found and the network it came from, so we can spot abuse and see which tools get used. It is not tied to an account.

Search crawlers use it to prioritise what to re-read, and they discount it when it is obviously wrong. A CMS that stamps today’s date on every page in every build is worse than no lastmod at all, because it trains the crawler to ignore the field. If yours updates honestly, it helps your genuinely-changed pages get recrawled sooner.