A♯m(maj7)♭5 / B♭m(maj7)♭5

4-note minor-major 7th flat 5 on A♯ / B♭A♯, C♯, E, A.

Press to hear the chord strummed low to high.

A diminished triad carrying a major seventh — rare and severe, the darkest corner of the minor-major family.

The notes

Pitches taken from the first fingering below — click any note to open its frequency page.

Interval formula

DegreeNoteWhat it is
1A♯root
♭3C♯minor third
♭5Eflat fifth (diminished)
7Amajor seventh

The formula reads in semitones above the root (A♯): 1, ♭3, ♭5, 7. A voicing may leave a tone out — often the fifth — but never adds one from outside this set.

Guitar fingerings · 4

1234
open position
5fr24311
from fret 5
6fr12311
from fret 6
8fr1243
from fret 8

Ukulele fingerings · 4

312
open position
31
open position
3fr1243
from fret 3
6fr1412
from fret 6

Read a diagram top-down: the thick bar is the nut, dots are where to press (the number is which finger), means play the open string, means don't play it. A bar across strings is a barre.

Other A♯ / B♭ chords

m(maj7)♭5 chords on every root