LargeXMLSitemap allows PHP developers to generate search engine XML sitemaps with millions of URLs. It automatically handles correct sizing, splitting, and compression of the generated XML file structure. Unlike other tools, LargeXMLSitemap does not crawl your site to generate an XML structure of your browseable URLs; it's a collection of PHP classes that can be used from within your site's code to generate these structures. If, for example, you have an online shopping site, it's very easy to create correctly structured, sized, and compressed XML sitemaps with the URLs to all your product pages. Customized versions of these classes are in production use on the MyHammer platform and are reliably generating sitemaps with millions of URLs each day.