the circle of fifths, with every key signature
the circle of fifths puts the twelve major keys in order of their sharps and flats, with each relative minor on the ring inside. musicians use it to read a key signature at a glance and to find the keys and chords closest to the one a score is in.
- clockwise adds a sharp; counterclockwise adds a flat.
- the inner ring is each key's relative minor, with the same signature.
- tap a key to see its signature on a staff.
explore the circle
select a key to light up its relative minor, its two neighbours and its key signature.
C major and A minor
no sharps or flats. the relative minor, A minor, shares this key signature.
next door on the circle: F major and G major. each differs from C major by one note.
how to read the circle of fifths
start at C major at the top, which has no sharps or flats. each step clockwise goes up a perfect fifth and adds one sharp: G has one, D has two, A has three, and so on round to C♯ major with seven. each step anticlockwise goes up a perfect fourth instead and adds one flat: F has one, B♭ has two, down to C♭ major with seven. at the bottom of the circle the two directions meet, so B and C♭, F♯ and G♭, and D♭ and C♯ are the same sounds written two ways.
the small figure outside each segment is the number of sharps or flats in that key. the inner ring holds the relative minor, which uses the same key signature and starts on the sixth note of the major scale.
key signatures and relative minors
| major key | relative minor | key signature | accidentals, in order |
|---|---|---|---|
| C major | A minor | none | none |
| G major | E minor | 1 sharp | F♯ |
| D major | B minor | 2 sharps | F♯ C♯ |
| A major | F♯ minor | 3 sharps | F♯ C♯ G♯ |
| E major | C♯ minor | 4 sharps | F♯ C♯ G♯ D♯ |
| B major | G♯ minor | 5 sharps | F♯ C♯ G♯ D♯ A♯ |
| F♯ major | D♯ minor | 6 sharps | F♯ C♯ G♯ D♯ A♯ E♯ |
| C♯ major | A♯ minor | 7 sharps | F♯ C♯ G♯ D♯ A♯ E♯ B♯ |
| F major | D minor | 1 flat | B♭ |
| B♭ major | G minor | 2 flats | B♭ E♭ |
| E♭ major | C minor | 3 flats | B♭ E♭ A♭ |
| A♭ major | F minor | 4 flats | B♭ E♭ A♭ D♭ |
| D♭ major | B♭ minor | 5 flats | B♭ E♭ A♭ D♭ G♭ |
| G♭ major | E♭ minor | 6 flats | B♭ E♭ A♭ D♭ G♭ C♭ |
| C♭ major | A♭ minor | 7 flats | B♭ E♭ A♭ D♭ G♭ C♭ F♭ |
naming a key from its signature
sharps always appear in the order F C G D A E B, and flats in the reverse order, B E A D G C F. for a sharp key, the last sharp is the seventh note of the scale, so the key is a half step above it: a signature ending on D♯ is E major. for a flat key, the second-to-last flat names the key: B♭ E♭ A♭ is E♭ major. F major, with its single flat, is the one to memorise. to tell the major key from its relative minor, look at how the music starts and ends and listen for a raised seventh, such as G♯ in A minor.
using the circle for chords
the three major chords of any major key sit side by side on the outer ring. in C major they are F, C and G, the IV, I and V chords. the minor chords of the same key sit just inside them: D minor, A minor and E minor. many progressions walk anticlockwise around the circle, one fifth down at a time. A minor to D minor to G to C is a common example, and jazz standards lean on the same motion as ii, V, I.
neighbouring keys differ by one note, so a piece that changes key often moves one step around the circle, from C major to G major or F major. a jump across the circle, from C to F♯, changes almost every note and sounds far more abrupt.
common questions
what is the circle of fifths?
a diagram of the 12 major keys arranged so that each one is a perfect fifth above the last, going clockwise from C. each step clockwise adds a sharp to the key signature, and each step counterclockwise adds a flat. the relative minor keys sit on the inner ring.
how do I find the relative minor of a key?
go down three half steps from the major key's tonic, or read the inner ring of the circle: A minor for C major, E minor for G major, D minor for F major. the two keys share the same key signature.
why is it called the circle of fifths?
because neighbouring keys are a perfect fifth apart, C to G to D and so on. after twelve fifths you are back at C, which closes the circle, with F♯ and G♭ as the same key at the bottom.
how do I use the circle of fifths to write chord progressions?
chords next to each other on the circle sound closely related. moving counterclockwise, such as D to G to C, gives the strong fifth-down motion of ii–V–I. the chord progression guide builds on it.
sources
- Wikipedia: circle of fifths
- Wikipedia: relative key
- Open Music Theory: major scales and key signatures
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