Abdim Piano Chord

A flat diminished is the Abdim piano chord. It has three notes: A flat, B and D. It is an A flat minor chord with the fifth lowered by one key.

1A♭3B5DC3C4

A♭ at the bottom, then B and D. Right hand 1-3-5, left hand 5-3-1. The black key is A♭.

How to play Abdim on piano, step by step

  1. Start on the A♭ below middle C. That is the lowest note of the chord.
  2. Thumb (1): A♭
  3. Middle finger (3): B
  4. Little finger (5): D
  5. Press them together with the right hand. The left hand plays the same notes with fingers 5, 3, 1 an octave lower, or just A♭ on its own as a bass note.

The middle and top notes are written B and D rather than C flat and E double flat. Those are the keys you actually press, and the names every chart uses.

Inversions of Abdim

The same 3 notes with a different one at the bottom. All of them are Abdim; which you play depends on what the hand is coming from. Tap any card to hear it.

First inversionB D A♭
Abdim piano chord diagram, first inversion, B D A♭
Lighter than root position and less final. A flat third in the bass tips the chord forward, which is why it usually sits between two other chords rather than at the end of a line.
Second inversionD A♭ B
Abdim piano chord diagram, second inversion, D A♭ B
Open and slightly unresolved. A fifth in the bass makes the chord sound like a step on the way somewhere, which is mostly how it is used.

If it sounds wrong

The top note is E flat
That gives A flat minor. A flat diminished needs D, the white key one lower.
The thumb slips off the black key
The root is the only black note here. Keep the hand far enough in that the thumb sits on it comfortably.
The chord sounds harsh
That is the point. Resolve it upward to A major, or back into A flat minor.

What makes it an Abdim

A♭ · B · D 1 ♭3 ♭5

A flat diminished is A flat, B and D: the root, the flat third and the flat fifth. Strictly the upper notes are C flat and E double flat, which are the keys called B and D.

It is the leading tone chord of A, and a passing chord in flat keys.

Abdim vs Abm

The top note. A flat minor has E flat; A flat diminished lowers it to D.

Both keep the A flat under the thumb, so only the little finger moves between them.

Questions about Abdim

Which notes are in a Abdim chord on piano?

A flat, B and D. It is a minor chord with the fifth lowered by one key.

What is the difference between Abdim and A flat minor?

The top note. A flat minor has a normal fifth; Abdim lowers it by one key to D. That single change turns a sad chord into a tense one.

How does a diminished chord resolve?

Usually up by one key. Abdim leans toward A major, and playing the two in a row is the quickest way to hear why: every note of the diminished chord is a half step or a whole step from where it wants to go.

Is Abdim hard to play?

No. It is three notes with an even shape, since a diminished triad is two minor thirds stacked. The intervals are the same size, which makes the hand position symmetrical and easy to remember.

Chords to learn next

Other Ab chords