G diminished chord on bass (Gdim)

Also called or written Gdim or

G diminished contains G, B♭, and D♭. The 3rd-fret shape is a one-finger-per-string stretch that sits low on the neck.

3frGD♭GB♭EADG
Positions on the neck1 of 4
Practice G diminished chord

How it is built

GRootB♭Minor thirdD♭Diminished fifth

Formula 1, ♭3, ♭5

Inversions

How do you play a G diminished chord on bass?

G diminished is played at the 3rd fret as 3 4 5 3: index finger on the E string at fret 3, ring finger on the A string at fret 4, pinky finger on the D string at fret 5 and middle finger on the G string at fret 3.

Full note and interval breakdown
StringFretFingerNote
4 (E)31G (1)
3 (A)43D♭ (♭5)
2 (D)54G (1)
1 (G)32B♭ (♭3)

IntermediateThe pinky must reach the 5th fret on the 2nd string while the middle finger holds the 3rd fret on the 1st string.

Gdim/B♭ inversion

G diminished is played at the 4th fret as 6 4 5 6: ring finger on the E string at fret 6, index finger on the A string at fret 4, middle finger on the D string at fret 5 and pinky finger on the G string at fret 6.

Full note and interval breakdown
StringFretFingerNote
4 (E)63B♭ (♭3)
3 (A)41D♭ (♭5)
2 (D)52G (1)
1 (G)64D♭ (♭5)

Gdim/D♭ inversion · fret 3

G diminished is played at the 3rd fret as × 4 5 3: middle finger on the A string at fret 4, ring finger on the D string at fret 5 and index finger on the G string at fret 3. The E string stays muted.

Full note and interval breakdown
StringFretFingerNote
4 (E)muted
3 (A)42D♭ (♭5)
2 (D)53G (1)
1 (G)31B♭ (♭3)

Gdim/D♭ inversion · fret 8

G diminished is played at the 8th fret as 9 10 8 ×: middle finger on the E string at fret 9, ring finger on the A string at fret 10 and index finger on the D string at fret 8. The G string stays muted.

Full note and interval breakdown
StringFretFingerNote
4 (E)92D♭ (♭5)
3 (A)103G (1)
2 (D)81B♭ (♭3)
1 (G)muted

Why it sounds like that

G diminished is built from the formula 1, ♭3, ♭5. The ♭5 interval gives the chord its tense, unstable quality. Compare G minor, which raises the fifth to D.

What goes wrong with G diminished?

  • Letting the pinky collapse onto the 1st string mutes the G.
  • Pressing the index finger too flat on the 4th string buzzes against the fret.
  • Arching the ring finger too high pulls the 3rd string sharp.

When to use it

G diminished works as a passing chord between G minor and B♭ major, or over an F natural minor line. The ♭5 interval creates a tritone that pulls toward the next chord, suiting jazz walk-ups and metal riffs.

Changing to and from G diminished

  • Sliding the shape down two frets to the 1st fret gives F diminished.
  • Move to G minor by raising the 2nd string one fret to the 6th fret.

Which voicing to use

The 3rd-fret shape puts G in the bass for a root-position sound. The Gdim/B♭ inversion at the 6th fret places B♭ in the bass, which softens the chord's bite.

Other G chords

Common questions

How do I write G diminished?

Write G° or Gdim. The root is G, and the chord is spelled G–B♭–D♭.

Why does G diminished sound unstable?

The ♭5 interval creates a tritone with the root, which wants to resolve. This tension is what gives diminished chords their forward drive.

Can I use G diminished in place of G minor?

Only when you want that darker, more dissonant color. G diminished lowers the fifth, so it clashes with melodies that expect the perfect fifth D.