How to validate a Google Sitemap

There is an easy and fast way to accomplish this. Libxml2 is the XML C parser and toolkit of Gnome (http://xmlsoft.org/). If libxml2 is installed on your system you can use the command line tool xmllint to validate your google sitemap. This is done by validating your sitemap file against the Google Sitemap XML schema. Here are two examples:

Download the XML schema from http://www.google.com/schemas/sitemap/0.84/sitemap.xsd and run

xmllint --schema sitemap.xsd yoursitemap.xml

Or fetch the schema directly from Google

xmllint --schema http://www.google.com/schemas/sitemap/0.84/sitemap.xsd yoursitemap.xml

Some useful options
--help
--debug