Mixed in Key - Mixed In Key is award-winning DJ software that gives you the #1 technique of the world's best...
beaTunes - Smart software for library management, music analysis, and playlist creation. For Windows and macOS.
KeyFinder - Key estimation software for DJs
Tunebat - A browser based song key and bpm database. Supplies compatible songs for harmonic mixing.
foo_bpm - A component for calculating the BPMs (beats per minute) of any tracks in Foobar2000.
TuneUp - TuneUp makes your music fresh and clean!