Circle of Fifths

It is a circular diagram that arranges the 12 keys by perfect-fifth intervals. Going clockwise adds a sharp; counter-clockwise adds a flat. It helps you know each key signature, find chords that sound good together and understand the relationships between keys.

Click any major key (outer ring) or minor key (inner ring). You will see its key signature, the scale notes, the diatonic chords (I, ii, iii, IV, V, vi, vii°) and its relative. Press play to hear the scale or the I–IV–V–I progression.

For composing and building progressions (neighboring chords on the circle sound natural), for transposing songs, for knowing how many sharps or flats a key has, and for memorizing key signatures quickly.

Every major key shares its key signature with a minor key: its relative minor, which starts on the sixth degree (for example, C major and A minor share the same notes). On the circle, the relative minor sits on the inner ring, right inside its major.

Yes, it is completely free, no sign-up, and works on PC, tablet and mobile right in the browser, with sound included.