What a sitemap does
A sitemap is the list of pages you want crawlers to know about. Without one, search engines discover pages by following links and can miss anything more than a click or two deep.
The mistakes that matter
The common failures are quiet ones. The file exists but robots.txt never mentions it. It lists pages that redirect or 404. It went stale the day the site was rebuilt. Each one wastes crawl budget you never see.
How this checker works
We read your robots.txt for a Sitemap line, fall back to the standard address, and parse whatever we find with the same reader Navlio uses in its site reports. At most three requests touch your site.