How to read the circle of fifths
The twelve major keys sit around the outside, each a fifth above the one before it: C at the top, then G, D, A, E and B going clockwise. Each step clockwise adds one sharp to the key signature; each step anticlockwise adds one flat: F, Bb, Eb, Ab. The inner ring holds the relative minor keys, and the outer band counts the sharps or flats in each key.
Neighbouring keys share six of their seven notes, which is why keys next to each other sound close and keys across the circle sound far apart.
Key signatures: sharps and flats per key
Sharps are added in the order F C G D A E B, flats in the reverse order B E A D G C F. The number on the circle tells you how many; the order tells you which.
| Major key | Relative minor | Sharps or flats | Accidentals |
|---|---|---|---|
| C | Am | 0 | — |
| G | Em | 1 | F♯ |
| D | Bm | 2 | F♯ C♯ |
| A | F#m | 3 | F♯ C♯ G♯ |
| E | C#m | 4 | F♯ C♯ G♯ D♯ |
| B | Abm (G#m) | 5 | F♯ C♯ G♯ D♯ A♯ |
| F# | Ebm (D#m) | 6 | F♯ C♯ G♯ D♯ A♯ E♯ |
| Db | Bbm | 5 | B♭ E♭ A♭ D♭ G♭ |
| Ab | Fm | 4 | B♭ E♭ A♭ D♭ |
| Eb | Cm | 3 | B♭ E♭ A♭ |
| Bb | Gm | 2 | B♭ E♭ |
| F | Dm | 1 | B♭ |
Three keys at the bottom of the circle have a second spelling: B is also Cb (7 flats), F# is also Gb (6 flats) and Db is also C# (7 sharps). The same goes for their minors: Abm is written G#m with 5 sharps, and Ebm is written D#m with 6 sharps.
Relative minor keys
Every major key shares its notes and key signature with one minor key, its relative minor. The relative minor starts on the 6th note of the major scale, three semitones below the tonic: C major and A minor, G major and E minor. On the circle it sits directly inside its major key; the Major and Minor switch above jumps between the two.
Chords in a key and fifths progressions
Build a chord on each note of the scale using only notes from the key and you get seven chords: three major (I, IV, V), three minor (ii, iii, vi) and one diminished (vii°). In C major that is C, Dm, Em, F, G, Am and B°. On the circle, the six major and minor chords are the key and its two neighbours, outside and inside.
The pad colours group the chords by job: red for the tonic chords (I, iii, vi) that feel at rest, orange for the subdominant chords (ii, IV) that move away, yellow for the dominant chords (V, vii°) that pull back home.
Progressions travel around that group. I–V–vi–IV (C G Am F) is the four-chord loop behind many pop songs. ii–V–I (Dm G C) steps anticlockwise by fifths and lands home. In a minor key, i–VI–III–VII (Am F C G) and i–iv–v (Am Dm Em) do the same job.
Changing key (modulation)
The closer two keys are on the circle, the smoother a change between them. A step to a neighbour (C to G or F) changes one note, and four chords belong to both keys: C, Em, G and Am for C to G. Any of them can pivot into the new key. Moving to the relative minor changes no notes at all, only the home chord. A jump across the circle changes most of the notes and sounds like a fresh start.
Circle of fifths vs the Camelot wheel
The Camelot wheel is the DJ version of the same circle. It numbers the positions 1 to 12 and marks minor keys A and major keys B, so C major is 8B and A minor is 8A. Mixing to the same number, the other letter, or one step either way works for the same reason neighbouring keys share chords here.