Triads
A♭ diminished chord
Tense and unstable — it usually wants to resolve up by a half step.
A♭dim is the vii° chord in A major. In minor keys: ii° in F♯ minor.
- Notes
- A♭C♭E𝄫
- Formula
- 1♭3♭5
- Built from
- root · minor 3rd · diminished 5th
How to play A♭dim
About the A♭ diminished chord
Playing it
On guitar, A♭dim has an open-position shape, 420404, using four fingers alongside the open strings.
On piano, A♭dim has one black key (A♭) and two white keys.
On ukulele the usual A♭dim shape is 4242, using four fingers.
Related chords
Move a single note and A♭dim becomes a different chord: raise E𝄫 to E♭ for A♭m, add G♭ for A♭m7♭5 and add G𝄫 for A♭dim7.
Where you’ll hear it
Notice the C♭ in A♭dim (A♭ C♭ E𝄫): each note of the chord takes its own letter (A–C–E), so the minor 3rd has to be written C♭ rather than B — the same key on a piano, spelled to fit the chord.
