What Is an XML Sitemap Checker?
An XML sitemap checker fetches and parses a domain's sitemap to report the total URL count, last-modified dates, sitemap type, and sub-sitemaps. A well-maintained sitemap directly improves crawl efficiency — it tells Googlebot exactly which pages exist and when they were last updated, prioritizing crawl budget on your most important content.
Using Sitemaps to Identify Crawl Issues
Compare your sitemap URL count against the number of indexed pages in Google Search Console. If your sitemap lists 500 pages but only 200 are indexed, you have a crawlability issue worth investigating — likely caused by noindex tags, robots.txt blocks, duplicate content, or thin content. The gap between sitemap count and index count is a key diagnostic metric.
Expired Domain Sitemap Research
The Wayback Machine archives sitemaps from expired domains. Checking a domain's historical sitemap reveals exactly what content it had and which sections were most active. This intelligence helps you assess whether the domain's backlinks came from genuine content — critical due diligence before acquisition.