Free sitemap checker and validator

Enter a website or sitemap address. The checker finds the sitemap, reads it and lists every problem it finds.

Free, no account needed. Updated October 29, 2026.

Short answer

A sitemap checker reads your XML sitemap the way a crawler does and reports what is wrong with it. This one finds the sitemap from robots.txt or the usual paths, counts the URLs, reads up to 10 child sitemaps and flags wrong hosts, bad dates, duplicates and files that are not XML.

How to use the sitemap checker

Enter an address. Type your home page (example.com) to let the checker find the sitemap, or paste the sitemap URL itself (example.com/sitemap.xml) to check one file.
Select Check sitemap. The checker reads robots.txt, then tries each sitemap address until one answers with XML.
Fix the problems from the top down. Errors come first, then warnings, then notes. Each line says what is wrong, how many URLs it affects and up to three examples.

What the checker reads and checks

The checker reads a sitemap the way a crawler does. It only fetches public addresses on the host you enter, and it stops reading a file after 2 MB. For a sitemap index, it reads the first 10 child sitemaps.

Where the sitemap is. The checker looks at the Sitemap: lines in robots.txt first, then /sitemap.xml, /sitemap_index.xml and /sitemap-index.xml.
Whether the file is a sitemap. The root must be <urlset> (a list of pages) or <sitemapindex> (a list of other sitemaps). An HTML page at /sitemap.xml is a common mistake.
Protocol limits. One file may list up to 50,000 URLs and be up to 50 MB uncompressed.
Each URL entry. Every <loc> must be a full URL on the same host. The checker also flags http and https mixed together, duplicate URLs, and <lastmod> dates that are in the wrong format or in the future.

What the result means

Errors stop crawlers from using some or all of the sitemap: no sitemap, a file that is not XML, URLs on another host, relative URLs, child sitemaps that fail to load, or more URLs than the protocol allows. Fix these first.

Warnings do not break the file, but they make it less useful. A crawler that sees future or malformed dates often ignores <lastmod> for the whole site. Duplicates hide your real page count. A sitemap that robots.txt does not list is hard for many crawlers to find.

Notes are for information. Missing <lastmod> values are allowed. They only mean that crawlers cannot tell which pages changed.

Who reads your sitemap

Search engines use a sitemap to find pages that few links point to, and <lastmod> to decide which pages to read again. Search engines can find pages without a sitemap, but a large site or a new site gets read faster with one.

Search engines are not the only readers. AI assistants that search the web, and the crawlers that feed them, also start from robots.txt and the sitemap. So do tools that import a website into a chatbot. When Paperlink AI imports a docs site or help center, its crawler reads robots.txt, then the sitemap. It follows links on the pages only when the sitemap lists no pages in the import's scope. So when a sitemap exists, a page that it leaves out is not imported. The help center import page explains the full order.

How to fix the most common problems

The sitemap is not listed in robots.txt

Add one line with the full URL anywhere in robots.txt. You can list more than one sitemap.

text

User-agent: *
Allow: /

Sitemap: https://example.com/sitemap.xml

The lastmod dates are wrong

Many sites set every <lastmod> to the time the sitemap was generated. Crawlers learn that the dates mean nothing and stop using them. Set the date from the page content: the date of the last real edit. Use 2026-10-29 or 2026-10-29T14:30:00+00:00.

URLs on another host or scheme

A sitemap on www.example.com lists only www.example.com pages. Pick one host and one scheme (normally https://), redirect the others to it, and list only the canonical URL of each page.

The sitemap is too big

Split the URLs into files of up to 50,000 URLs each, for example one per section of the site. Then list the files in a sitemap index:

xml

<?xml version="1.0" encoding="UTF-8"?>
<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <sitemap><loc>https://example.com/sitemap-docs.xml</loc></sitemap>
  <sitemap><loc>https://example.com/sitemap-blog.xml</loc></sitemap>
</sitemapindex>

How many pages does a website have?

The URL count in the result is the quickest answer: it is the number of pages the site asks crawlers to read. It is not always the full count. A sitemap can leave out pages the owner forgot, or list pages that redirect. For a site without a sitemap, or to compare the two numbers, crawl it with the sitemap generator, which follows links and counts the pages it reaches.

A short sitemap checklist

The sitemap returns status 200 and an XML content type.
robots.txt lists it with a full URL.
It lists only canonical, indexable pages: no redirects, no 404s, no pages blocked by robots.txt.
Every URL uses the same host and https.
<lastmod> matches the last real change of each page.
Your CMS updates it when you add or remove a page.

After you fix the sitemap, check robots.txt too. A sitemap cannot help with pages that robots.txt blocks. If you want to see how a customer support chatbot reads your site, read how to turn your help center into an AI chatbot.

Frequently asked questions

How do I find the sitemap of a website?

Open the site's robots.txt (example.com/robots.txt) and look for a line that starts with "Sitemap:". If there is none, try example.com/sitemap.xml and example.com/sitemap_index.xml. This checker tries all three for you, in that order.

What makes a sitemap invalid?

A sitemap is invalid when it is not well-formed XML, does not use a <urlset> or <sitemapindex> root, lists more than 50,000 URLs in one file, or lists URLs on another host. Wrong <lastmod> dates and duplicate URLs do not break the file, but they make crawlers trust it less.

Does my sitemap need to be listed in robots.txt?

No, but it helps. Search engines find a sitemap at the usual path or through their webmaster tools. Other crawlers, including many AI crawlers, only find it when robots.txt lists it. Add one "Sitemap:" line with the full URL.

What format should lastmod use?

Use the W3C Datetime format: a date such as 2026-10-29, or a date and time with a time zone such as 2026-10-29T14:30:00+00:00. Set it to the date the page content last changed, not the date the sitemap was generated.

How many URLs can one sitemap have?

One sitemap file can list up to 50,000 URLs and be up to 50 MB uncompressed. A larger site splits its URLs across several sitemaps and lists them in a sitemap index file.

Does this checker store the sitemap?

The result is cached for one hour so that a second check of the same address is fast. We do not keep the sitemap after that, and we never record the address you checked in analytics. If you select Create share link, we keep the report (not the file) for 30 days so the link works.

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