Ukulele · half diminished seventh
B♭m7♭5 Chord on Ukulele
Bb Half-Diminished 7th (m7♭5) is Bb, Db, Fb, Ab — the 1-b3-b5-b7 pattern of a half diminished seventh chord. Here is the shape, the audio, and what usually goes wrong.
Good news: Bbm7b5 has an open shape on ukulele, so you can play it without barring anything. Start there and work up the neck later.
Start here — Movable m7b5 Shape (1st fret)
Open shape — open strings ring right through it and there is nothing to barre. If you only learn one, learn this one.
What beginners get wrong
Moving in and out of it
The shape above: Movable m7b5 Shape (1st fret) — open position, so several strings ring unfretted — barred at fret 1.
Listening: each shape above has its own play button, and each one plays the notes that shape actually produces — not a generic triad.
Bbm7b5 on other instruments
Same notes, different hands. Every link below is a real page with diagrams and audio.
Guitar
B♭m7♭5 on guitar
2 voicings · easiest is intermediate
Piano
B♭m7♭5 on piano
3 voicings · easiest is intermediate
Bass
B♭m7♭5 on bass
1 voicing · easiest is advanced
Mandolin
B♭m7♭5 on mandolin
1 voicing · easiest is intermediate
Banjo
B♭m7♭5 on banjo
1 voicing · easiest is advanced
Or see Bb Half-Diminished 7th (m7♭5) on every instrument at once.
Chords next door
Same root, different colour — and all of them playable on ukulele.
Bbm7b5 on Ukulele — questions people ask
What is the easiest way to play Bbm7b5 on ukulele?
“Movable m7b5 Shape (1st fret)” — which we rate intermediate — is the easiest Bbm7b5 shape on ukulele. Open shape — open strings ring right through it and there is nothing to barre. If you only learn one, learn this one.
What notes are in the Bb Half-Diminished 7th (m7♭5) chord?
Bb Half-Diminished 7th (m7♭5) is Bb, Db, Fb, Ab — the 1-b3-b5-b7 interval pattern of a half diminished seventh chord. Every voicing on this page uses those notes and nothing else; they just appear in a different order and octave.
What can I play instead of Bbm7b5?
The nearest stand-ins on ukulele that keep the same root are Bbsus4, Bbsus2, Bb. They keep the root and the fifth and only change what sits in the middle, so most songs still work — but check the swap against the melody, because the note you removed may be the one the tune is singing.
Can I play Bbm7b5 on other instruments?
Yes. Bbm7b5 is the same set of notes everywhere; only the fingering changes. This site has diagrams and audio for it on guitar, piano, bass, mandolin, banjo.
Learn the theory behind Bbm7b5
The shape gets your fingers there. These explain why it sounds the way it does.
Barre Chords — The Wall Every Guitarist Climbs
This one asks for a barre. The article is the fix for the buzzing and the aching hand.
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Functional Harmony: Three Roles, One Engine
Diminished chords are almost always doing a job. This explains which one.
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Cadences — The Four Ways a Phrase Ends
Where all that tension goes — how the chord resolves into the next one.
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