Adim Piano Chord

A diminished is the Adim piano chord. It has three notes: A, C and E flat. It is an A minor chord with the fifth lowered by one key.

1A3C5E♭C3C4

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

How to play Adim 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): C
  4. Little finger (5): E♭
  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.

A minor is the first minor chord most people learn, so this is a good place to meet the diminished sound: one finger moves and the whole character changes.

Inversions of Adim

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

First inversionC E♭ A
Adim piano chord diagram, first inversion, C E♭ 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 inversionE♭ A C
Adim piano chord diagram, second inversion, E♭ A C
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
That gives A minor. A diminished needs E flat, the black key just below it.
The little finger is weak on the black key
It has to reach deeper than the other fingers. Let the hand lean outward rather than pressing harder.
The chord sounds unstable
That is what it is for. Play B flat major after it and the tension clears.

What makes it an Adim

A · C · E♭ 1 ♭3 ♭5

A diminished is A, C and E flat: the root, the flat third and the flat fifth.

It is the leading tone chord of B flat, and it appears as a passing chord in the keys around it. Like every diminished triad it is two minor thirds stacked.

Adim vs Am

The top note. A minor has E, a white key; A diminished has E flat, the black key below it.

The rest of the chord is identical, so the change is one finger moving from white to black.

Questions about Adim

Which notes are in a Adim chord on piano?

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

What is the difference between Adim and A minor?

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

How does a diminished chord resolve?

Usually up by one key. Adim leans toward B flat 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 Adim 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 A chords