Polychrome Computer

Sing your melody, find the key and work out the chords. Play it anywhere an idea finds you. Real chords, real voicings and real songwriting.

This was built to be a compact, portable instrument for musicians and songwriters of all levels. Beginners will enjoy the ability to quickly go from a sung melody to useable chords for their first songs. Experts will appreciate the alternate chord voicing, offline use and the ability to work on songs anywhere.

Free to use. No email or account signup necessary.

How it works:
1. Tap to start, then sing or hum a melody.
2. Hold each note for a moment and Polychrome Computer will identify the key, then the eight chords of that key appear.
3. Work out the chord progression that fits your melody with the eight chord buttons and shift chord voicings as you go.
4. Or work without key detection and find the key and octave that suits you best.