Best Free Sitemap Validators (2026): What Each One Actually Checks

"Is my sitemap valid?" can mean three different things. Is the XML well-formed and does it follow the sitemap protocol? Are the URLs inside it the right ones (status 200, indexable, canonical)? And has Google actually read it? No single free tool answers all three, which is why the six tools below are grouped by what they actually check.

The rules a validator should know

• Up to 50,000 URLs and 50 MB (uncompressed) per sitemap file; larger sites use a sitemap index.
• Absolute URLs in <loc>, with special characters such as & escaped.
• <lastmod> in W3C date format (for example 2026-10-13), reflecting real content changes.
• Google ignores <priority> and <changefreq>, so validators that score them are checking for other search engines at best.

Quick comparison (October 2026)

The tools, by what they are best at

Google Search Console — best for knowing what Google did

The Sitemaps report is the only tool here that shows Google’s side: submission history, whether the sitemap could be fetched, parsing errors, and how many URLs were discovered. Google’s help page adds that you can filter the Page indexing report by sitemap to see how many listed URLs are indexed. You need a verified property, and owner permissions to submit; without them you can list the sitemap in robots.txt instead. It is not a pre-publish validator: you only see problems after Google has tried to read the file.

Patrick Stox XML Sitemap Validator — best for finding exactly what is broken

Patrick Stox’s validator is free with no sign-up. You can paste XML, upload a .xml or .xml.gz file, or fetch by URL through the site’s rate-limited proxy. Validation runs in your browser, and the result lists every problem by severity with line numbers, a health score and CSV/JSON export. The page is honest about the limit: a valid file can still list redirects or noindexed pages, which only a crawl of the URLs reveals.

Swetrix Sitemap Validator — best for a clear protocol checklist

Swetrix’s validator fetches a sitemap by URL and, according to its page, checks well-formed XML, encoding, required tags, URL format, duplicate entries, W3C dates in lastmod, priority and changefreq values, file size and URL count limits, and sitemap index files. Results come with a preview of the URLs. Limits are not published.

Screaming Frog SEO Spider — best for checking the URLs inside

Screaming Frog’s sitemap audit guide says the free version can upload and analyse an XML sitemap in list mode, crawling up to 500 URLs. That shows status codes, redirects, noindex and canonicals for each listed URL. Comparing the sitemap against a full site crawl (to find orphan URLs or pages missing from the sitemap) requires a paid licence.

PromoPilot Sitemap Analyzer — best for a quick check from just a domain

Our Sitemap Analyzer accepts a domain or a sitemap URL. Given a domain, it looks for Sitemap: lines in robots.txt, then tries /sitemap.xml and /sitemap_index.xml. It checks that the XML parses, counts URLs, measures how many have lastmod and how fresh those dates are (updated in the last 90 days vs older than a year), counts priority tags and warns about the 50,000 URL and 50 MB limits. For a sitemap index it lists the child sitemaps. The table shows the first 100 URLs.

XML-Sitemaps.com validator — best for a fast format check

The XML-Sitemaps.com validator checks whether your sitemap is formatted correctly and reports problems before you submit it. The same site offers a sitemap generator that works without registration. The page also offers to ping Google; Google’s own recommendation is to submit through Search Console or list the sitemap in robots.txt.

Common sitemap problems and which tool catches them

• An unescaped & in a URL breaks the whole file. Every validator here catches it; Patrick Stox’s shows the line.
• Redirected, noindexed or 404 URLs in the sitemap. The XML is valid, so syntax validators pass it; you need a crawl of the URLs or the Page indexing report in Search Console.
• A staging or http hostname left in the list after a migration. Visible in any URL preview; easy to miss in a file with thousands of rows.
• The same lastmod on every URL, usually the date the sitemap was generated. It is valid, but it tells search engines nothing. In our analyzer this shows up as almost every URL “updated in the last 90 days” on a site that rarely changes.
• A sitemap that returns an HTML page (a login screen, a 404 template with status 200) instead of XML. Search Console reports it as a fetch or parsing error.

How to choose

1. Before you submit: a syntax validator (Patrick Stox or Swetrix), or ours if you only know the domain.
2. After a migration or a big release: crawl the listed URLs (Screaming Frog list mode, or our HTTP status checker for a handful) — the sitemap should contain only 200, indexable, canonical URLs.
3. Always: submit in Search Console and check the report a few days later.
4. No sitemap yet: build one with our sitemap generator and make sure robots.txt points to it.

What our tool does not do

• It checks that the XML is well-formed, not full schema (XSD) validation, and it does not report line numbers.
• It does not open child sitemaps of an index automatically: run each child separately. Gzipped .xml.gz files are not unpacked.
• It does not check the status codes or indexability of the listed URLs.

Related reading: sitemap.xml checks and common errors, checking robots.txt and how to check if a page is indexed.