XML Sitemap Generator and Validator

The Sitemaps protocol is short. A sitemap is a UTF-8 XML file with a <urlset> root in the sitemaps.org namespace and one <url> per page, each with a required <loc>:

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>https://example.com/search?q=shoes&amp;sort=new</loc>
    <lastmod>2026-10-01</lastmod>
  </url>
</urlset>

The namespace is an identifier, not a link, so it must be exactly http://www.sitemaps.org/schemas/sitemap/0.9; the https:// version is a common mistake. An unescaped & in a query string makes the whole file invalid XML. The generator escapes every value, removes #fragments (crawlers ignore them), percent-encodes spaces and accents, and lists each URL once.

Only <lastmod> does, for Google. Google says it ignores <priority> and <changefreq>, and uses <lastmod> when it is consistently and verifiably accurate. Set it to the date of the last significant change to the page's content, not the day you generated the sitemap; a footer copyright update doesn't count.

Dates use W3C Datetime:

2026-10-14                   date only (most common)
2026-10-14T09:30+02:00       with time: minutes and a time zone
2026-10-14T07:30:00Z         seconds, in UTC

A time always needs a time zone, and formats such as 14/10/2026 are invalid. When a CMS export has times without a zone (2026-10-14 09:30:00), the generator keeps only the date rather than guess the offset.

List every language version of a page inside each version's <url> entry, including itself, with <xhtml:link> and the xhtml namespace. Google's rules say links that don't point at each other are ignored, so every version must list every other version.

In the generator, give your CSV a header of language codes; each row becomes one page in several languages:

en,de,x-default,lastmod
https://example.com/,https://example.com/de/,https://example.com/,2026-10-01

Codes are an ISO 639-1 language, optionally a region from ISO 3166-1 alpha-2 (de-CH), or x-default for the fallback page. Two classic mistakes are caught: en-UK (the code is GB) and numeric regions such as es-419, which Google doesn't support.

Split the URLs into several sitemaps and list them in a sitemap index, which has the same limits. The generator does it automatically, at 50,000 URLs or 50 MB per file:

<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <sitemap>
    <loc>https://example.com/sitemap-1.xml</loc>
    <lastmod>2026-10-14</lastmod>
  </sitemap>
</sitemapindex>

Google requires the listed sitemaps to sit on the same site as the index, in its folder or below it. Upload every file, then submit only sitemap-index.xml. In an index, <lastmod> is when that sitemap file changed, not its pages.

Only the canonical URLs you want in search results: pages that return 200, aren't redirects, aren't marked noindex and aren't blocked in robots.txt. Listing duplicates, filtered views or tracking variants (?utm_source=…) wastes crawling and sends mixed signals.

A sitemap at the root covers the whole site. Tell search engines where it is with a Sitemap: line in robots.txt (the robots.txt generator writes it) and by submitting it in Google Search Console and Bing Webmaster Tools.