Sitemap Index

Definition

A sitemap index is an XML file that lists multiple individual sitemaps for a website. It's used when a site has more than 50,000 URLs or when individual sitemap files exceed 50MB — the limits imposed by the Sitemaps protocol. The sitemap index file follows a specific XML structure with <sitemapindex> as the root element, containing <sitemap> entries that point to individual sitemap files. Each entry includes a <loc> (URL of the sitemap) and optional <lastmod> (last modification date). Best practice is to organize sitemaps by content type: one for pages, one for blog posts, one for products, etc. This makes it easier to monitor indexing status per content type in Google Search Console. Submit the sitemap index URL (not individual sitemaps) to Search Console.