Mozilla Sunbird® is a cross-platform calendar application, built upon Mozilla Toolkit. The goal is to bring Mozilla-style ease-of-use to your calendar, without tying you to a particular storage solution.

It was developed as a stand-alone version of the Lightning calendar and scheduling extension for Mozilla Thunderbird. A portable apps version is available.

It is no longer being actively developed by Mozilla. Resources have been concentrated on the integrated Lightning calendar project that works with Mozilla Thunderbird.

Operating systems: Windows, Linux, BSD UNIX, Mac OS X, Solaris, OpenSolaris and OS/2
Platforms: 32 bit or 64 bit (Linux)
Screen libraries: GTK+