Gadget, a part of the SIMILE Widgets family of tools, is an open source command line XML inspector for generating useful summaries from large amounts of well-formed XML data. It is particularly valuable when exploring, migrating or cleaning XML, in addition to evaluating schema emergence. This tool require a Java 1.4 or later compatible virtual machine and Maven 2.0 or above to run.

Gadget is no longer maintained, but information about it is still available via the Internet Archive.