Chord · 7ths

B♭m7♭5 — B♭ Half-Diminished

B♭m7♭5 is the B♭ half-diminished chord. It is built on the root B♭ with minor 3rd (D♭), diminished 5th (F♭) and minor 7th (A♭) above it — the formula 1 ♭3 ♭5 ♭7, sounding the notes B♭ D♭ F♭ A♭. On the piano it sits at Bb (octave 3) and above in the library's voicing; the same 4 notes in any octave are still B♭m7♭5.

Root
B♭
Quality
Half-Diminished
Formula
1 ♭3 ♭5 ♭7
Notes
B♭ D♭ F♭ A♭

On the keyboard

B♭m7♭5 on the piano keyboard: B♭ D♭ F♭ A♭1235B♭D♭F♭A♭

Right-hand fingering for this voicing: 1–2–3–5 (1 is the thumb).

The notes of B♭m7♭5

DegreeNoteInterval from the rootPitch
1B♭rootB♭3
♭3D♭minor 3rdD♭4
♭5F♭diminished 5thF♭4
♭7A♭minor 7thA♭4

Other 7ths on B♭

Half-Diminished chords on every root

Part of the chord reference. See also the scales and the keys.