A♭ diminished 7th chord on guitar (A♭dim7)

Also called or written A♭dim7 or A♭°7

A♭ diminished 7th contains A♭, C♭, E♭♭ and G♭♭. The 3rd fret shape is a barre chord that requires a strong index finger.

3frA♭E♭♭G♭♭C♭E♭♭EADGBE
Positions on the neck1 of 5
Practice A♭ diminished 7th chord

How it is built

A♭RootC♭Minor thirdE♭♭Diminished fifthG♭♭Minor seventh

Formula 1, ♭3, ♭5, ♭♭7

Inversions
  • Root positionA♭–C♭–E♭♭–G♭♭A♭dim74-5-3-4-3-×
  • First inversionC♭–E♭♭–G♭♭–A♭A♭dim7/C♭×-2-0-1-0-1
  • Second inversionE♭♭–G♭♭–A♭–C♭A♭dim7/E♭♭×-×-0-1-0-1
  • Third inversionG♭♭–A♭–C♭–E♭♭A♭dim7/G♭♭1-2-0-1-0-1

How do you play an A♭ diminished 7th chord on guitar?

A♭ diminished 7th is played at the 3rd fret as 4 5 3 4 3 ×: barre your index finger across fret 3, middle finger on the low E string at fret 4, pinky finger on the A string at fret 5 and ring finger on the G string at fret 4. The high e string stays muted.

Full note and interval breakdown
StringFretFingerNote
6 (E)42A♭ (1)
5 (A)54E♭♭ (♭5)
4 (D)31 (barre)G♭♭ (6)
3 (G)43C♭ (♭3)
2 (B)31 (barre)E♭♭ (♭5)
1 (e)muted

AdvancedThe 3rd fret barre requires the index finger to fret the D and B strings cleanly while the pinky reaches the 5th fret on the A string.

4th fret

A♭ diminished 7th is played at the 4th fret as 4 5 6 4 6 4: barre your index finger across fret 4, middle finger on the A string at fret 5, ring finger on the D string at fret 6 and pinky finger on the B string at fret 6.

Full note and interval breakdown
StringFretFingerNote
6 (E)41 (barre)A♭ (1)
5 (A)52E♭♭ (♭5)
4 (D)63A♭ (1)
3 (G)41 (barre)C♭ (♭3)
2 (B)64G♭♭ (6)
1 (e)41 (barre)A♭ (1)

6th fret

A♭ diminished 7th is played at the 6th fret as × × 6 7 6 7: index finger on the D string at fret 6, ring finger on the G string at fret 7, middle finger on the B string at fret 6 and pinky finger on the high e string at fret 7. The low E and A strings stay muted.

Full note and interval breakdown
StringFretFingerNote
6 (E)muted
5 (A)muted
4 (D)61A♭ (1)
3 (G)73E♭♭ (♭5)
2 (B)62G♭♭ (6)
1 (e)74C♭ (♭3)

9th fret

A♭ diminished 7th is played at the 9th fret as × 11 9 10 9 10: barre your index finger across fret 9, pinky finger on the A string at fret 11, middle finger on the G string at fret 10 and ring finger on the high e string at fret 10. The low E string stays muted.

Full note and interval breakdown
StringFretFingerNote
6 (E)muted
5 (A)114A♭ (1)
4 (D)91 (barre)C♭ (♭3)
3 (G)102G♭♭ (6)
2 (B)91 (barre)A♭ (1)
1 (e)103E♭♭ (♭5)

10th fret

A♭ diminished 7th is played at the 10th fret as × 11 12 10 12 10: barre your index finger across fret 10, middle finger on the A string at fret 11, ring finger on the D string at fret 12 and pinky finger on the B string at fret 12. The low E string stays muted.

Full note and interval breakdown
StringFretFingerNote
6 (E)muted
5 (A)112A♭ (1)
4 (D)123E♭♭ (♭5)
3 (G)101 (barre)G♭♭ (6)
2 (B)124C♭ (♭3)
1 (e)101 (barre)E♭♭ (♭5)

Why it sounds like that

A♭ diminished 7th is built from the intervals 1, ♭3, ♭5 and ♭♭7. The ♭♭7, a diminished seventh above the root, creates the chord's distinctive tension. Compare it with A♭ minor 7th flat 5th, which has a minor seventh instead.

What goes wrong with A♭ diminished 7th?

  • Letting the high E string ring instead of muting it.
  • Not pressing the barre hard enough, causing the B string to buzz.
  • Flattening the ring finger onto the B string and muting the barre note.

When to use it

A♭ diminished 7th often resolves to B♭ minor or B♭ major. It suits tense jazz and classical passages.

Changing to and from A♭ diminished 7th

  • Sliding the shape down two frets to the 1st fret gives F♯ diminished 7th.
  • From B♭ minor, move the pinky from the 6th fret of the A string to the 5th fret and add the barre.

Which voicing to use

The 3rd fret barre keeps the root A♭ in the bass and is the default voicing. The 9th fret barre shape moves the root to the low E string for a heavier sound.

Other A♭ chords

Common questions

How is A♭ diminished 7th written?

A♭ diminished 7th is written A♭°7 or A♭dim7. The ASCII root spelling is Ab. It is also spelled G♯ in enharmonic notation for the same sounding root.

What is the difference between A♭ diminished 7th and A♭ minor 7th flat 5th?

A♭ diminished 7th has a diminished seventh (G♭♭), while A♭ minor 7th flat 5th has a minor seventh (G♭). The diminished seventh makes the chord fully diminished.

Why is the high E string muted in the 3rd fret shape?

The open high E is not a chord tone of A♭ diminished 7th. Muting it keeps the voicing clean and the bass note on A♭.