Sevenths
B half-diminished 7th chord
Dark and unresolved; often the ii chord in a minor key.
Bm7♭5 is the viiø7 chord in C major. In minor keys: iiø7 in A minor.
- Notes
- BDFA
- Formula
- 1♭3♭5♭7
- Built from
- root · minor 3rd · diminished 5th · minor 7th
How to play Bm7♭5
About the B half-diminished 7th chord
Playing it
On guitar, Bm7♭5 has an open-position shape, x20201, using three fingers alongside the open strings. Don’t strum the low E string.
On piano, Bm7♭5 sits entirely on white keys.
On ukulele the usual Bm7♭5 shape is 4210, using three fingers.
Related chords
Take away the root and the other three notes form Dm (D F A) — so you can think of Bm7♭5 as Dm with B added underneath.
Bm7♭5 contains exactly the same notes as Dm6. Which name fits depends on which note is in the bass and what key you’re in.
Move a single note and Bm7♭5 becomes a different chord: raise F to F♯ for Bm7, drop the A for Bdim and lower A to A♭ for Bdim7.
