How to Play A#dim on Piano
The A# Diminished chord sounds tense and unsettled. It stacks 3 notes: A# – C# – E.
Two stacked minor thirds. Its fifth is squeezed a semitone flat, so the chord has no stable footing and wants to move.
Notes in A#dim
| Note | Interval | Finger |
|---|---|---|
| A#A#4 | Root | 1 |
| C#C#5 | Minor 3rd | 3 |
| EE5 | Diminished 5th | 5 |
How to Play
Right Hand
Place your thumb (finger 1) on A#. Use finger 3 on C# and finger 5 on E.
Where it sits
2 notes of this chord (A#, C#) are on black keys, so play it a little further back on the keys than an all-white shape.
Press all 3 keys at the same time. Keep your wrist relaxed and your fingers curved. The blue dots on the piano below show exactly which keys to press — they turn green when you play the right note.