Root position
G – Bb – DbThe root G is the lowest note. This is the shape most people learn first.
3 notes · 1 · ♭3 · ♭5
G Diminished Piano Chord (Gdim)
Gdim is built from G, Bb and Db — the formula 1 · ♭3 · ♭5, or 3 and 6 semitones above G. The shape uses 1 white and 2 black keys, and you can hear it, invert it and compare it below.
Chord
G Diminished
Notes
G · A# · C#Formula
1 · ♭3 · ♭5Right hand
1 · 3 · 5C
D
E
F
G
A
B
C
C#
D#
F#
G#
A#
Choose a chord, then play it. Finger numbers run from thumb (1) to little finger (5).
The finder above already holds Gdim. Press P or the Play chord button to hear G, Bb, Db sounded together, then change the root or the chord type to compare it with something else.
Chord tones
The notes in Gdim
A diminished triad is two minor thirds stacked on top of each other, which squeezes the fifth a semitone flat. The result is tense and unresolved. It appears on the seventh degree of a major scale and on the second degree of a minor key, and it usually leads straight back to a more stable chord.
| Note | Interval | Degree | Semitones | Right hand |
|---|---|---|---|---|
| Gwhite key | Root | 1 | 0 | 1 · thumb |
| Bbblack key | Minor third | ♭3 | 3 | 3 · middle finger |
| Dbblack key | Diminished fifth | ♭5 | 6 | 5 · little finger |
Step by step
How to play Gdim on piano
- Find G: it is the white key between the first and second black keys of a group of three.
- Build upwards from G using 3 and 6 semitones to reach Bb and Db.
- With the right hand, place finger 1 on G, finger 3 on Bb and finger 5 on Db. Keep the wrist level and the knuckles rounded.
- Move your hand a little further in towards the fallboard so the black keys sit comfortably under your fingers.
- Play the notes together, then one at a time from the bottom up, and listen to how Gdim settles.
- Try first inversion as well: Bb – Db – G. Inversions let you change chords without jumping around the keyboard.
Inversions
Gdim in 3 positions
An inversion keeps the same 3 notes and simply moves the lowest one up an octave. Learning them means you can change chords with small hand movements instead of jumping to a new part of the keyboard.
First inversion
Bb – Db – GBb is the lowest note, so the minor third sits in the bass and the notes below it move up an octave.
Second inversion
Db – G – BbDb is the lowest note, so the diminished fifth sits in the bass and the notes below it move up an octave.
In context
Which keys contain Gdim
In A♭ major the chord functions as vii°. Altogether it is produced by the scales of 3 keys, so learning it once pays off in several places.
- A♭ majorvii°
- F minorii°
- G♯ harmonic minorvii°
Chord tones are spelled by the degree they occupy, so the third of a minor chord is written as a flat rather than a sharp even though it is the same key on the piano. A double sharp such as F## means the key one whole tone above F.
Compare
Gdim against G minor
Gdim and G minor share G and Bb. Moving the perfect fifth D down 1 semitone to the diminished fifth Db turns G minor into Gdim.
Practise the pair together: hold the shared notes G, Bb still and move only the one finger. Hearing that single change is the quickest way to recognise the two chords by ear.
Open G minor →Good questions
Gdim questions
What notes are in the Gdim chord?
Gdim contains G, Bb and Db. Counted from the root, that is the formula 1 · ♭3 · ♭5, or 3 and 6 semitones above G.
What is the right-hand fingering for Gdim?
A comfortable beginner fingering is 1 (thumb) on G, 3 (middle finger) on Bb and 5 (little finger) on Db. Finger numbers run from the thumb (1) to the little finger (5), and they change once you start using inversions.
How is Gdim different from G minor?
Gdim and G minor share G and Bb. Moving the perfect fifth D down 1 semitone to the diminished fifth Db turns G minor into Gdim.
Which keys use the Gdim chord?
It occurs naturally in A♭ major (vii°), F minor (ii°) and G♯ harmonic minor (vii°). The roman numeral shows which degree of the key the chord is built on.
What are the inversions of Gdim?
root position is G – Bb – Db, first inversion is Bb – Db – G and second inversion is Db – G – Bb. Every inversion holds the same notes; only the lowest one changes.