What a sitemap checker does
An XML sitemap tells search engines which URLs you want crawled. When the file is missing, returns an error, or is filled with duplicates and wrong dates, crawlers quietly skip it and new pages take longer to be discovered. A sitemap checker downloads the file the same way a crawler would and reports what went wrong.
This sitemap checker starts from robots.txt, follows every Sitemap: declaration, opens sitemap index files and gzip-compressed sitemaps, and validates each file against the sitemap protocol. The result lists errors (problems that can stop a sitemap from being read), warnings (problems that reduce its usefulness) and notes.
How to check your sitemap online
You do not need to know where the sitemap lives. Enter the domain and the checker finds it.
1. Enter a domain or sitemap URL
Use a bare domain like example.com to run discovery, or paste a sitemap URL to validate that file and its children.
2. Let the checker find every sitemap
It reads robots.txt first, then tries /sitemap.xml, /sitemap_index.xml and /wp-sitemap.xml, and expands sitemap indexes up to two levels deep.
3. Fix the issues by severity
Start with errors, then warnings. Each issue shows the affected file, how many times it occurs, examples and a suggested fix.
What the sitemap validator checks
Every file is checked for availability, format and content quality.
Availability
HTTP status, redirects, timeouts, HTML pages served in place of XML, and the Content-Type header.
Format and limits
A valid <urlset> or <sitemapindex> root, absolute <loc> URLs, at most 50,000 entries and 50 MB uncompressed per file, and correct index nesting.
URL quality
Duplicate URLs, URLs on another domain, http:// URLs on an HTTPS site, and missing, malformed or future lastmod dates.
Discovery
Whether robots.txt declares the sitemap, so search engines can find it without a manual submission.
Sitemap files, sitemap indexes and robots.txt
Small sites usually publish one sitemap file at /sitemap.xml. It is a <urlset> document with one <url> entry per page, each holding a <loc> address and an optional <lastmod> date. Search engines read it, compare it with what they already know, and schedule new or changed URLs for crawling.
Larger sites split their URLs into several files and publish a sitemap index: a <sitemapindex> document that lists the location of each child sitemap. WordPress, Shopify and most frameworks generate this structure automatically, often grouped by post type, product collection or date. When you check a domain, the sitemap checker opens the index and every child file it lists, so one check covers the whole structure rather than only the top-level file.
robots.txt connects the two. A single line such as Sitemap: https://example.com/sitemap_index.xml lets every crawler find the sitemap without a manual submission, and it is the first place this checker looks. If robots.txt has no declaration, the checker falls back to common paths and reports the missing line as a warning, because other crawlers and SEO tools rely on it too.
When to run a sitemap check
After a site migration, a CMS or plugin change, a new deployment, a domain or HTTPS switch, and whenever Search Console shows a sitemap as couldn't fetch or has errors.
Reading the result
Fix errors first: a file that fails to load or parse is ignored completely. Warnings such as duplicates or http:// URLs waste crawl attention but do not block the rest of the file.
How to fix common sitemap errors
Most sitemap problems come from the generator rather than the server. A few patterns cover the majority of failed checks.
“Couldn't fetch” or HTML instead of XML
If the URL returns your homepage or a 404 template, the sitemap route is not deployed or a rewrite catches it. Open the URL in a private window and confirm it returns XML with status 200.
Duplicate and http:// URLs
Two plugins or routes often generate overlapping sitemaps. Keep one generator, and make sure it outputs the canonical https:// URL that matches your canonical tags.
Invalid or future lastmod
Write lastmod from the content's real modification date in W3C format. Setting it to the build time or a future date teaches search engines to ignore it.
Too many URLs in one file
Split large sitemaps by section or date and reference the parts from one sitemap index. Each part stays under 50,000 URLs and 50 MB.
Check once or monitor continuously
A sitemap check answers whether the sitemap is valid right now. It is the right tool after a migration, a CMS change or a new deployment, and when Search Console reports that a sitemap could not be read.
To see which pages a site adds or removes over time, including competitors, use Sitemap Monitor. It rescans public sitemaps every six hours and keeps a history of URL changes you can read on the web or through MCP.
Sitemap checker FAQ
How do I check if my sitemap is working?
Enter your domain above. The checker finds the sitemap through robots.txt or standard paths, downloads every file and reports whether each one loads with status 200 and parses as a valid sitemap.
How do I find a website's sitemap?
Look for Sitemap: lines in /robots.txt, then try /sitemap.xml, /sitemap_index.xml or /wp-sitemap.xml. This tool runs those steps automatically and lists every file it finds.
What makes an XML sitemap valid?
A UTF-8 XML file with a <urlset> or <sitemapindex> root, absolute <loc> URLs on the same site, at most 50,000 URLs and 50 MB uncompressed per file, and optional lastmod dates in W3C format.
How many URLs can a sitemap contain?
50,000 URLs or 50 MB uncompressed per file. Larger sites split their URLs across several sitemaps listed in a sitemap index.
Does lastmod matter?
Google uses lastmod when it is consistently accurate. Missing lastmod is not an error, but wrong or future dates reduce trust in the whole file.
Can it check .gz sitemaps and sitemap indexes?
Yes. Gzip-compressed sitemaps are decompressed, and sitemap index files are expanded up to two levels, reading up to 25 files per check.
Does this submit my sitemap to Google?
No. The checker only reads public files. Submit the sitemap in Google Search Console, or declare it in robots.txt so crawlers find it.
Is the sitemap checker free?
Yes. No sign-up is needed. To prevent abuse, each visitor can run a limited number of checks per minute, and checked sites are not stored.