G diminished chord (Gdim)
Gdim is G, B♭ and D♭: 1–♭3–♭5 built on G. See and hear it on all three instruments below.
On guitar
x-x-5-3-2-3 · movable · medium
- Notes
- G · B♭ · D♭
- Formula
- 1 · ♭3 · ♭5
- First shape
- x-x-5-3-2-3
Gdim on guitar: every shape, finger by finger
On piano
root position · G–B♭–D♭ · right hand 1-3-5
- Notes
- G · B♭ · D♭
- Formula
- 1 · ♭3 · ♭5
Gdim on piano: fingering and inversions
On ukulele
0-1-3-1 · open · easy
- Notes
- G · B♭ · D♭
- Formula
- 1 · ♭3 · ♭5
- First shape
- 0-1-3-1
Where Gdim usually goes next
Here's what the hand does on the most common changes, on guitar and on piano.
- Gdim → A♭ (leads up a half step)
Guitar: Gdim (x-x-5-3-2-3) to A♭ (4-6-6-5-4-4): the index finger lays across the low E to high E strings at the 4th fret, the middle finger goes to the G string, 5th fret, your ring finger lands on the A string, 6th fret. No finger can stay, so practice lifting all of them together and landing the new shape as a unit.
Piano: Gdim to A♭: play A♭ in root position (A♭–C–E♭), while G moves up to A♭, B♭ up to C and D♭ up to E♭. A♭ - Gdim → G♯m (leads up a half step)
Guitar: Gdim (x-x-5-3-2-3) to G♯m (4-6-6-4-4-4): the index finger lays across the low E to high E strings at the 4th fret, your middle finger lands on the A string, 6th fret, the ring finger goes to the D string, 6th fret. No finger can stay, so practice lifting all of them together and landing the new shape as a unit.
Piano: Gdim to G♯m: play G♯m in root position (G♯–B–D♯), while G moves up to G♯, B♭ up to B and D♭ up to D♯. G♯m - Gdim → Cm (iii in A♭ major)
Guitar: Gdim (x-x-5-3-2-3) to Cm (x-3-1-0-1-3): move the index finger to the D string, 1st fret, move the middle finger to the B string, 1st fret, the ring finger goes to the A string, 3rd fret. Nothing carries over, so drill it slowly, lifting and landing all fingers at once. G carries over from one chord to the other.
Piano: Gdim to Cm: play Cm in 2nd inversion (G–C–E♭) and G stays under the same finger, while B♭ moves up to C and D♭ up to E♭. Cm
How Gdim is built
Gdim is a diminished triad: two minor thirds stacked. It sounds tense and unstable and rarely stays long. Its most common job is to lead up a half step, so Gdim usually moves to A♭ or G♯m.
From G, go 3 half steps up to B♭ then 3 half steps up to D♭.
| Note | Role | Half steps | Hear it |
|---|---|---|---|
| G | root | 0 | |
| B♭ | minor third | 3 | |
| D♭ | diminished fifth | 6 |
Keys and progressions with Gdim
Gdim belongs to 2 keys: vii° in A♭ major and ii° in F minor.
Chords close to Gdim
- Gdim and Gm differ by one note: D♭ in Gdim, D in Gm. They share G and B♭. Gm
Chords that share most of their notes with Gdim: C♯dim7, E♭7, Edim7, Gdim7, Gm7♭5, B♭m6.
Every G chord
G diminished chord: questions
What notes are in the G diminished chord?
G, B♭ and D♭. Gdim is built 1–♭3–♭5 from G: B♭ is the minor third and D♭ is the diminished fifth.
How do you play Gdim on guitar?
The usual shape is x-x-5-3-2-3 (movable). All 4 guitar shapes.
How do you play Gdim on piano?
Play G, B♭ and D♭ with right-hand fingers 1-3-5. G sits between the first two black keys of the three. Inversions and left hand.
How do you play Gdim on ukulele?
0-1-3-1 in standard GCEA tuning. More ukulele shapes.
What key is Gdim in?
Gdim belongs to 2 keys: vii° in A♭ major and ii° in F minor.
What's the difference between Gdim and Gm?
Gdim and Gm differ by one note: D♭ in Gdim, D in Gm. They share G and B♭.
All three instruments are drawn and played from G, B♭ and D♭ by the same engine. Updated September 2026.