Learn Music Theory
Interactively
Four tools to help you understand keys, chords, progressions, and the frequency spectrum — whether you're starting out or sharpening your craft.
Click any key on the circle to instantly see its sharps or flats, relative minor, scale notes, and the seven diatonic chords that live inside it.
Select any major key and see its sharps or flats drawn on treble and bass clef staves, plus all seven diatonic chords with Roman numeral analysis.
Load a preset progression or build your own by clicking diatonic chords. Set your key and tempo, then hit play to hear it through your browser using Web Audio.
An interactive EQ cheat sheet showing where each instrument lives in the frequency spectrum. Hover for EQ tips, click to hear a sine tone at the center frequency.