How to Play G#m7b5 on Piano
The G# Half-Diminished 7th chord sounds hollow and searching. It stacks 4 notes: G# – B – D – F#.
The half-diminished seventh, written either with a flat five or with a slashed circle. A diminished triad with a plain minor seventh on top rather than a diminished one, which is what separates it from the fully diminished chord. It is the ii of every minor key, so almost every minor ii-V starts here.
Notes in G#m7b5
| Note | Interval | RH | LH |
|---|---|---|---|
| G#G#4 | RootR | 1 | 5 |
| BB4 | Minor 3rdb3 | 2 | 4 |
| DD5 | Diminished 5thb5 | 3 | 3 |
| F#F#5 | Minor 7thb7 | 5 | 1 |
How to Play
One hand, 4 notes
Right hand, low note to high: fingers 1-2-3-5 on G#, B, D, F#. The left hand plays the same shape mirrored, 5-4-3-1, usually an octave or two lower.
Shell voicing
Root, third and seventh: G#, B, F#, left hand 5-3-1. Those three notes are what make this chord the chord it is, so a jazz player holds them in the left hand and keeps the right hand free for the melody.
Where it sits
2 notes of this chord (G#, F#) are on black keys, so play it a little further back on the keys than an all-white shape.
Opens a block chord drill for G#m7b5. More drills, from broken chords to inversions, are further down the page.
Practice Exercises
Play each one to hear it, then open it in the practice player, which shows the notes coming toward you and checks what you play on a MIDI keyboard or the on-screen piano.
Block Chord
Press all 4 notes (G#, B, D, F#) at the same time. Hold for 4 beats, release, then repeat 8 times. Focus on pressing every key at exactly the same moment with even volume.
Broken Chord (Arpeggio)
Play each note one at a time. Go up, then back down:
G# → B → D → F# → F# → D → B → G#
Keep a steady rhythm. Once comfortable, try speeding up gradually.
Inversions and Slash Chords
The same 4 notes rearranged so a different one sits at the bottom. This is the same idea as a slash chord: G#m7b5/B is simply G#m7b5 with B in the bass. Learning to move between them is what stops your hand jumping around the keyboard.
| Inversion | Written | Notes | RH |
|---|---|---|---|
| Root position | G#m7b5 | G# – B – D – F# | 1-2-3-5 |
| 1st inversion | G#m7b5/B | B – D – F# – G# | 1-2-4-5 |
| 2nd inversion | G#m7b5/D | D – F# – G# – B | 1-2-3-5 |
| 3rd inversion | G#m7b5/F# | F# – G# – B – D | 1-2-3-5 |
Two-Hand: Bass + Chord
Left hand: play G# one octave lower as a single bass note. Right hand: play G#, B, D, F#. Play the bass note first, then the chord, like a simple accompaniment pattern. Repeat until it feels natural.
When to use each slash chord
Puts the third in the bass, which is the usual way to walk a bass line by step between two chords a third apart.
Puts the fifth in the bass. This is the shape that keeps a pedal-like bass under a changing harmony, and the one most often written with a slash in pop and worship charts.
Puts the seventh in the bass, which pulls the bass line downward by step into the next chord.
Chords You Can Play Instead of G#m7b5
These share most of their notes with G#m7b5, so any of them can stand in for it without breaking the harmony. Swapping one in is the quickest way to make a progression you already know sound different.
Keys and Scales for G#m7b5
Keys G#m7b5 belongs to
Every note of G#m7b5 is in each of these keys, and the numeral says the job it does there.
Scales to play over it
None of these produce a note that clashes with G#m7b5. The ones built on G# itself are the ones to learn, because that rule then works in every key.
- G# Bluesbuilt on G#
- B Dorianthe parent key
- F# Natural Minorthe parent key
Half-Diminished 7th Chords in Every Key
The same shape moved to another root. Once you can hear what a half-diminished 7th chord does, the work left is finding it under the hand in the other eleven keys.
Other G# Chords
Every other chord in the library built on G#: what G#m7b5 becomes when a note is added, moved or taken away.