Where should the sitemap live?

Anywhere, as long as robots.txt declares it. /sitemap.xml is convention rather than requirement, and the Sitemap: line is what removes the guesswork.

How many sitemaps should I have?

One, until it hits 50,000 URLs or 50 MB - then split it and add a sitemap index. Large sites often split by section anyway, so coverage problems are easier to localise.

Does this check the URLs inside it?

It checks they are absolute and on the right host. Whether each one returns 200, is indexable and is not a redirect needs a crawl of every URL - that is the full audit.

Free tools

XML sitemap checker

Give us a site or a sitemap URL. If you give us the site we find the sitemap the way a crawler does - robots.txt first, then the usual location - and validate what we find.

Free, no account, no card. One URL at a time.

What this checks

Where it is: Declared in robots.txt, or found at /sitemap.xml. A sitemap nobody can find does nothing.
That it is XML: Some servers answer an HTML 404 page with a 200, which looks fine until you parse it.
Index or urlset: A sitemap index is listed with the sitemaps it points at; a urlset is counted.
The protocol's limits: 50,000 URLs and 50 MB uncompressed per file.
Relative URLs and other hosts: Every <loc> must be absolute, and a sitemap may only list URLs on the host serving it.

Why it matters

A sitemap does not make pages rank, and it does help pages get found - particularly deep pages, new pages, and pages with few internal links pointing at them. It is a hint about what exists, not an instruction about what matters.

The failure that costs the most is silent: a sitemap listing URLs that redirect, or that carry noindex, or that were deleted months ago. Google reads it, follows what is in it, and quietly trusts the file less.

That comparison needs the pages fetched, not just the sitemap parsed - which is where a full crawl comes in. This checks the file itself is valid and findable, which is the half that has to be right first.

Questions

Where should the sitemap live?: Anywhere, as long as robots.txt declares it. /sitemap.xml is convention rather than requirement, and the Sitemap: line is what removes the guesswork.
How many sitemaps should I have?: One, until it hits 50,000 URLs or 50 MB - then split it and add a sitemap index. Large sites often split by section anyway, so coverage problems are easier to localise.
Does this check the URLs inside it?: It checks they are absolute and on the right host. Whether each one returns 200, is indexable and is not a redirect needs a crawl of every URL - that is the full audit.

One URL is a spot check

The full audit covers pages missing from the sitemap, sitemap URLs that redirect or 404, and invalid lastmod values - across every page it crawls, with a score and a ranked list of what to fix first.

Audit your site free How the audit works