The notes of D diminished
D diminished has three notes, D, F and A♭: F is a minor 3rd above D and A♭ is a diminished 5th above D. That gives the formula 1 ♭3 ♭5, two minor thirds stacked: a root, a minor third and a diminished fifth (6 half steps).
How it sounds and where it’s used
A diminished chord sounds tense and unstable: it’s two minor thirds stacked, with a tritone between the outer notes, so it never sounds like an ending. It wants to move, usually up a half step to the chord a step above, which is why it appears as vii° in a major key and as a passing chord. You’ll meet D diminished most as vii° in E♭ major and ii° in C minor.
- As vii° it leads up a half step to E♭: D rises to E♭, so it resolves to E♭ major or E♭ minor.
- Its three notes are the top of B♭7 (B♭, D, F and A♭): a dominant 7th without its root, which is why it pulls the same way.
- Start from D minor and lower the fifth, A to A♭, to get it.
Fingering
The thumb and little finger take the outer notes. Where two notes are a fourth apart rather than a third, the finger in between is skipped, which is why the inversions change the middle finger. In 2nd inversion the right thumb lands on a black key: move the whole hand a little further in towards the fallboard, so the fingers on white keys stay on them.
| Position | Notes | Right hand | Left hand |
|---|---|---|---|
| Root position | D F A♭ | 1-3-5 | 5-3-1 |
| 1st inversion | F A♭ D | 1-2-5 | 5-3-1 |
| 2nd inversion | A♭ D F | 1-3-5 | 5-2-1 |
Fingers count from the thumb (1) to the little finger (5). Shown low to high, so the left hand starts with 5.
Inversions
The same three notes can be stacked with any of them lowest. 1st inversion puts the third at the bottom: F, A♭ and D, written Ddim/F. 2nd inversion puts the fifth at the bottom: A♭, D and F, written Ddim/A♭. Whatever is on top, the chord is still D diminished: the lowest note only changes its colour. Pianists choose the position that is nearest to the chord before, so the hand moves by a step instead of jumping.
Keys with D diminished
Ddim is built from the notes of these keys, where it is the chord on the degree shown:
A key marked harmonic minor uses the raised 7th of that minor scale, as minor-key music does for its V and vii° chords.
Finding it fast
Count half steps from D: 3 and then 3 again (F 3 half steps above D and A♭ 3 half steps above F). Or play the minor chord and move the top note down one key. In root position its keys are white, white, black. E diminished and A diminished have the same shape on the keys, so learn them together.
To read it on the page as quickly, practise the shapes with the chord reading quiz, and see how the notes are counted in intervals.