F-flat major

F♭ major

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

F-flat major is a theoretical key based on F♭, consisting of the pitches F♭, G♭, A♭, B, C♭, D♭, and E♭. Its key signature has six flats and one double flat.

Its relative minor is D♭ minor, usually replaced by C♯ minor (see reason below) and its parallel minor is F♭ minor, usually replaced by E minor, since F♭ minor's four double-flats make it generally impractical to use.

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Wikipedia