IzPack is an open source software installer generator that targets the Java platform. It generates installers that fit in single JAR archives. As such, IzPack-generated installers are cross-platform: the same installer works on any operating system that has a working Java Runtime Environment. IzPack itself is a command-line utility, but a Java Swing based front end application, PackJacket, exists, which aims to create a simpler way to make IzPack-generated installers. IzPack is released under the terms of the liberal Apache License version 2.0.