Interactive Circle of Fifths
How to use
- Click any major key on the outer ring or minor key on the inner ring.
- The info panel shows the key signature, the relative minor, and the seven diatonic chords in that key.
- Click any chord chip to hear it.
- Hit Play this key to hear the I-IV-V-I cadence in the chosen key.
- Click any common progression to hear songwriting templates that work in this key.
- Toggle between triads and 7th chords for a richer harmonic vocabulary.
What is the circle of fifths?
The circle of fifths is the most useful single diagram in Western music theory. It arranges the twelve major keys around a clock face — moving clockwise, each key's tonic is a perfect fifth higher than the last. The amount of sharps in the key signature increases as you go clockwise (G has one sharp, D has two, A has three, and so on); the amount of flats increases as you go counterclockwise (F has one flat, B♭ has two, E♭ has three).
Inside the outer ring sits each major key's relative minor — the minor key that uses exactly the same notes. C major and A minor both use the seven natural notes; G major and E minor share one sharp. That's why two songs in those keys can borrow each other's chords without sounding strange.
For songwriting, the circle of fifths is a roadmap. Most chord progressions move "around the circle" — by perfect fifths, by step, or by jumping to a relative minor. The closer two keys are on the circle, the more chords they share, and the easier it is to modulate between them mid-song. Use this tool to find chords that feel related, plan key changes, or just memorize how the keys connect.
FAQs
What's the difference between the circle of fifths and the circle of fourths?
It's the same circle read in two directions. Going clockwise, each step is a perfect fifth up; going counterclockwise, each step is a perfect fourth up. (Up a fifth and up a fourth are inverses — they add up to an octave.) Some teachers call it the circle of fourths because the counterclockwise direction matches how chord progressions typically resolve (V → I is a fall by a fifth, which is the same as a rise by a fourth).
Why is C major at the top?
By convention. C major has no sharps or flats, so it's the natural "starting point" — putting it at 12 o'clock makes the symmetry of the circle visually obvious.
How do I use this for songwriting?
Pick the key your song is in, look at the diatonic chords, and you have a palette that's guaranteed to sound "in key." Want to add a borrowed chord? Look at the keys directly adjacent on the circle — those are the most natural places to grab chords from. Want to modulate? Move the clockwise neighbor's V chord into your song and let it pull you into the new key.
What are relative minors?
A relative minor is the minor key that shares its key signature with a given major key. C major and A minor both use the natural notes — they're relatives. The relative minor always sits a minor third (3 semitones) below the major's tonic, and on this circle it's the inner-ring key that lines up with the outer-ring key.
What does "diatonic" mean?
"Diatonic" just means "of the key." A diatonic chord is one built using only the notes of that key's scale. In a major scale you get a major triad on the I, two minors on the ii and iii, a major on the IV and V, a minor on the vi, and a diminished on the vii. These seven chords are what you'd call "in key."