Validator easily checks one XML file or a thousand.
-Terse, text-based validation report.
-Validates common XML files without need for an Internet connection.
-Native support for DocBook, DITA, TEI, SMIL, MathML, SVG, WAP/WML, and more.
-Provides several XHTML correctness checks beyond simple validation.
-Optional command-line interface.
-Automatically skips non-XML files.
-Simple "delete it and it's gone" uninstall.
-Drag-and-drop installation on Mac OS X.