Why it matters
A sitemap is the list of URLs you want search engines and AI crawlers to find. When it's broken, it usually fails quietly: an unescaped & stops the parser halfway, a CMS serves an HTML error page at /sitemap.xml, or URLs on another host are ignored. Search Console reports some of this days later and without line numbers.
This validator reads the file the way a strict XML parser does and checks each entry against the sitemaps.org protocol and the extensions Google documents for images, video, news and hreflang. It follows sitemap indexes to their children, unzips .gz files in your browser, charts lastmod dates by month so stale sections stand out, and exports every URL for checking elsewhere.
How it works
- InputA sitemap or index, pasted or fetched
- In your browserChecked against the sitemaps.org protocol
- OutputErrors by line, child sitemaps and a fixed file
Where it fits in a designer's workflow
- Plan
- Design
- Build
- Test
- Launch
By the numbers
Show the numbers as a table
| Line | Level | Problem |
|---|---|---|
| 10 | error | Unescaped & (write &). Parsers stop at this line. |
| 9 | warning | lastmod has a time but no time zone; add Z or +01:00. |
| 14 | error | changefreq “sometimes” isn't one of always, hourly, daily, weekly, monthly, yearly, never. |
| 14 | error | priority “1.5” must be between 0.0 and 1.0. |
| 27 | error | shop.example.com isn't the sitemap's host (www.example.co.uk). Sitemaps can only list URLs on their own host unless you prove ownership of both. |
| 27 | warning | lastmod 2027-03-01 is in the future. Google ignores lastmod values it can't trust. |
| 24 | warning | Duplicate URL (first on line 20): https://www.example.co.uk/guides/oak-care |
How to use it
- Paste the XML, open a .xml or .xml.gz file, or fetch the sitemap's address.
- Fix errors from the top: an XML error early in the file hides everything after it.
- Check the lastmod chart for sections that never change.
- Download the URL list as CSV.
FAQ
How many URLs can a sitemap hold?
50,000 URLs and 50 MB uncompressed per file. Bigger sites split into several files listed in a sitemap index.
Do changefreq and priority matter?
Google ignores both. Bing reads them loosely. lastmod matters, as long as it's accurate.
Can a sitemap list URLs on another domain?
Only if you've proved you own both sites (for example in Search Console, or through robots.txt on the other site). Otherwise they're ignored.
Is my sitemap uploaded?
Pasted or opened files are read on your device. A fetched sitemap is read once by leej.uk's fetcher, which keeps no content.
