Scale degrees · B major

The ♭5 of B is F

The ♭5 (flat five, written b5) of B is F: a diminished fifth above the root.

B — the root, 1F — the ♭5

How to find it

Count letters first, the root included: B, C, D, E, F. A 5th lands on F.

Then the sound: a diminished fifth is 6 semitones above B, which is exactly where F is — no sharp or flat needed.

Where you meet it

The ♭5 halves the octave: a tritone above B. It is the 5th of the half-diminished and the diminished chord.

In Bm7♭5:

B · D · F · A

The ♭5 in every key

KeyThe ♭5
CG♭
GD♭
DA♭
AE♭
EB♭
BF
F♯C
D♭A𝄫
A♭E𝄫
E♭B𝄫
B♭F♭
FC♭

Every degree of B

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