Sitemap Index Generator

How to use

1. 1Paste your sub-sitemap URLs into the input, one per line. The five sample lines (sitemap-pages.xml, sitemap-blog.xml, and so on) show the formats accepted.
2. 2Optional: write a per-line lastmod after a tab, a pipe (|), or a comma. The date can be YYYY, YYYY-MM, YYYY-MM-DD, or a full RFC 3339 timestamp.
3. 3Set the shared lastmod on the right when most rows share a date. Pick Omit lastmod, Use today (UTC), or Use custom date. Per-row values always win.
4. 4Read the validation panel for missing schemes, duplicates, non-XML extensions, mixed hostnames, or out-of-spec entries above 50,000 sub-sitemaps.
5. 5Click Copy XML to copy the generated sitemapindex, or Download sitemap.xml to save it as a file you can upload to your web root.
6. 6Copy the Sitemap: line at the bottom and add it to your robots.txt so search engines discover the index automatically.

About this tool

Sitemap Index Generator builds the meta-sitemap large sites need. The sitemaps.org 0.9 protocol caps every single sitemap.xml file at 50,000 URLs and 50 MB uncompressed bytes, so production sites split their listing into many sitemap files (sitemap-pages.xml, sitemap-blog.xml, sitemap-products-1.xml, and so on) and publish a sitemap index file at the web root that points at each one. This tool takes a list of those sub-sitemap URLs, validates each one with the native URL constructor, deduplicates by location, optionally autocompletes a missing scheme to https://, and emits a clean sitemapindex document that conforms to the sitemaps.org schema. Per-row lastmod can be written after a tab, a pipe, or a comma (https://example.com/sitemap-blog.xml | 2026-06-15) and is accepted in any W3C Datetime grammar the sitemaps spec allows: a year (2026), a year-month (2026-06), a date (2026-06-19), or a full RFC 3339 timestamp (2026-06-19T08:00:00Z, 2026-06-19T08:00:00+00:00). Per-row dates always override the shared lastmod control on the right, so you can keep one timestamp on every line, switch to today (UTC), or mix per-sitemap dates with a default. The validation panel flags missing schemes, non-XML paths, mixed hostnames (Google recommends every sub-sitemap and the index live on the same host), mixed http and https schemes, duplicates with the original line number, and out-of-spec entries when the listing grows past the 50,000-per-index sitemaps.org limit. Stats summarize the sub-sitemap count, on-wire byte size, unique hostnames, and an error and warning counter. The output panel renders the canonical XML with declaration, the sitemapindex root, and one sitemap block per row. A Copy XML button copies the document; a Download sitemap.xml button creates a local Blob so you can save the file directly to your web root or your sitemap directory. A reference robots.txt line is generated from the hostname of the first valid entry, ready to drop into the file your crawlers read first. Every byte is built in the browser. The pasted URL list, the validated rows, and the rendered XML stay on your device.

Free to use. Works in your browser. No signup, no login.