Interactive circle of fifths

How to use it

• Click any outer sector to select a major key.
• Click the inner sector for its relative minor.
• Use the panel to play the scale or a common progression in that key.
• Arrow keys move between adjacent keys; the whole tool is keyboard navigable.
• The URL updates as you go, so you can share or bookmark a specific key.

What the circle is telling you

Each clockwise step moves up a perfect fifth and adds one sharp. Each anticlockwise step moves up a fourth and adds one flat. Neighbouring keys share all but one note, which is why they sound related and why music modulates between them so readily.

The inner ring holds the relative minors. Each shares a key signature with the major key outside it, sitting a minor third below: A minor inside C major, E minor inside G major, and so on.

Four things to try

1. Find any key signature. Count steps from C. Three clockwise is A major, three sharps.
2. Find the three main chords. Any key plus its two neighbours gives you IV, I, and V.
3. Hear a ii–V–I. Three consecutive anticlockwise steps. This is the most common progression in jazz and one of the most common anywhere.
4. Find where a piece will modulate. Adjacent keys differ by one accidental, so they are the likely destinations.

Read more

The full explanation is in the circle of fifths explained simply. Instrument-specific versions: on the piano and on the guitar. There is also a printable circle of fifths PDF with both clefs marked.