Key Signitures

Key Signiture - guide

A key is the major or minor scale around which a piece of music revolves. Each major and minor key has an associated key signature that sharpens or flattens the notes which are used in its scale. The convention for the notation of key signatures follows the circle of fifths.

Circle of fifths


Info on Key Signitures


Key No' of sharps Sharp notes
C major 0
G major 1 F#
D major 2 F#, C#
A major 3 F#, C#, G#
E major 4 F#, C#, G#, D#
B major 5 F#, C#, G#, D#, A#
F# major 6 F#, C#, G#, D#, A#, E#
C# major 7 F#, C#, G#, D#, A#, E#, B#


Key No' of flats Flat notes
C major 0
F major 1 B♭
B♭ major 2 B♭, E♭
E♭ major 3 B♭, E♭, A♭
A♭ major 4 B♭, E♭, A♭, D♭
D♭ major 5 B♭, E♭, A♭, D♭, G♭
G♭ major 6 B♭, E♭, A♭, D♭, G♭, C♭
C♭ major 7 B♭, E♭, A♭, D♭, G♭, C♭, F♭

Notice in the table for sharps it shows that each scale starting on the fifth scale degree of the previous scale has one new sharp, added in the order given above. Where as in the table for flats each new scale starts a fifth below (or a fourth above) the previous one.

A key signature is not the same as a key; key signatures are merely notational devices. They are convenient principally for diatonic or tonal music.

For a given musical mode the key signature defines the diatonic scale that a piece of music uses. Most scales require that some notes be consistently sharped or flatted. For example, the only sharp in the G major scale is F sharp, so the key signature associated with the G major key is the one-sharp key signature.