# Sitemap.xml audit _Source: https://seomatrix.ai/tools/sitemap-audit/_ --- ## What it does A sitemap.xml checker validates the XML file that tells search engines and AI crawlers which URLs on your site exist and when they last changed. This tool counts the listed URLs, flags duplicates and missing lastmod dates, tests the file against the 50,000-URL / 50 MB protocol limit, and spot-checks whether listed URLs actually return 200 instead of 404. A clean, accurate sitemap is how crawlers discover and prioritize your pages — a broken or bloated one wastes crawl budget and leaves content undiscovered, which also keeps it out of AI answers. ## What it checks - **Sitemap reachability** — Whether /sitemap.xml (or the one in robots.txt) exists and returns well-formed XML — if the file is missing or malformed, crawlers get no map at all. - **URL count** — The total number of entries in the file, which shows your indexable coverage and how close you are to the per-file limit. - **50,000-URL / 50 MB limit** — The sitemaps.org cap on a single sitemap file; anything past it is ignored, so oversized sites must split into a sitemap index of multiple files. - **lastmod dates** — The timestamp signaling when a page changed — accurate values help crawlers prioritize re-crawling, while fake or blanket dates get discounted. - **Duplicate URLs** — The same URL listed more than once, which wastes crawl budget and usually points to a bug in how the sitemap is generated. - **200/404 spot-check** — Sampling the HTTP status of listed URLs; entries that return 404 or redirect mark the sitemap as stale and unreliable to crawlers. ## How to use it 1. Paste your domain (or the sitemap URL) and run the check. 2. Review the flagged issues — duplicates, missing or stale lastmod, over-limit counts, and any URLs returning 404. 3. Fix the sitemap: remove dead and duplicate URLs, correct lastmod, split into a sitemap index if you exceed 50,000 URLs, then resubmit it in Search Console. ## FAQ ### Where is my sitemap.xml? It's usually at yourdomain.com/sitemap.xml or referenced in robots.txt on a Sitemap: line. Large sites use a sitemap index file that points to several child sitemaps. ### How many URLs can a sitemap hold? A single sitemap file is capped at 50,000 URLs and 50 MB uncompressed. Beyond that, split your URLs across multiple sitemaps and list them in a sitemap index file. ### Does lastmod actually matter? Yes, when it's honest — Google uses an accurate to decide re-crawl priority. But consistently wrong dates, like today's date on every URL, get ignored and can erode trust in the file. ### Will a 404 in my sitemap hurt SEO? Listing URLs that return 404 or redirect signals a stale, low-quality sitemap, wasting crawl budget and slowing discovery of your real pages. Keep the sitemap to live, canonical, 200-status URLs only.