G-sharp major

G♯ major

Relative key	E♯ minor enharmonic: F minor
Parallel key	G♯ minor
Dominant key	D♯ major enharmonic: E♭ major
Subdominant	C♯ major enharmonic: D♭ major
Enharmonic	A♭ major
Component pitches
G♯, A♯, B♯, C♯, D♯, E♯, F, G♯

G-sharp major is a theoretical key based on the musical note G-sharp, consisting of the pitches G♯, A♯, B♯, C♯, D♯, E♯ and F. Its key signature has six sharps and one double sharp.

Although G♯ major is usually notated as the enharmonic key of A♭ major, because A♭ major has only four flats as opposed to G♯ major's eight sharps (including the F), it does appear as a secondary key area in several works in sharp keys - most notably in the Prelude and Fugue in C-sharp major from Johann Sebastian Bach's The Well-Tempered Clavier, Book 1. The G-sharp minor prelude (and, in some editions, the fugue) from the same set ends with a Picardy third, on a G-sharp major chord.

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