# D Half Diminished 7th piano chord (Dm7♭5)

Dm7♭5 contains D, F, A♭ and C. A diminished triad with the minor seventh added on top. A♭ is a black key; D, F and C are white.

- Canonical page: https://piano.org/chords/half-diminished/d/
- Entity: chord:half-diminished-7th:d
- Notes: D F A♭ C
- Formula: 1 ♭3 ♭5 ♭7
- Intervals from root: P1, m3, TT, m7
- Interval stack (semitones): 3 3 4
- Also written: Dm7♭5, Dm7b5, D half diminished 7th
- Parameters: A440, 12-TET, 165 mm octave, spans centre to centre

## Construction

| Degree | Note | Interval from root | Semitones |
| --- | --- | --- | --- |
| 1 | D | Perfect unison | 0 |
| ♭3 | F | Minor third | 3 |
| ♭5 | A♭ | Tritone | 6 |
| ♭7 | C | Minor seventh | 10 |

## Fingering

Rest your right hand over the notes with finger 1 on D, finger 2 on F, finger 3 on A♭, finger 5 on C. The left hand mirrors it.
Right hand 1-2-3-5, left hand 5-3-2-1. Source: piano.org fingering method v1.

## Inversions

| Position | Bass | Notes in order | Figured bass | Span |
| --- | --- | --- | --- | --- |
| Root position | D | D3 F3 A♭3 C4 | 7 | 10 st, 138 mm |
| First inversion (Dm7♭5/F) | F | F3 A♭3 C4 D4 | 6/5 | 9 st, 124 mm |
| Second inversion (Dm7♭5/A♭) | A♭ | A♭3 C4 D4 F4 | 4/3 | 9 st, 124 mm |
| Third inversion (Dm7♭5/C) | C | C4 D4 F4 A♭4 | 4/2 | 8 st, 110 mm |

## Voicings (10)

| Voicing | Notes | Span | Relation | Omits or adds |
| --- | --- | --- | --- | --- |
| Close, root position | D3 F3 A♭3 C4 | 10 st, 138 mm | identical | none |
| Close, first inversion | F3 A♭3 C4 D4 | 9 st, 124 mm | identical | none |
| Close, second inversion | A♭3 C4 D4 F4 | 9 st, 124 mm | identical | none |
| Close, third inversion | C4 D4 F4 A♭4 | 8 st, 110 mm | identical | none |
| Drop 2 | A♭2 D3 F3 C4 | 16 st, 220 mm | identical | none |
| Drop 3 | F2 D3 A♭3 C4 | 19 st, 261 mm | identical | none |
| Drop 2 and 4 | D2 A♭2 F3 C4 | 22 st, 303 mm | identical | none |
| Shell, root ♭7 ♭3 | D2 C3 F3 | 15 st, 206 mm | subset | omits A♭ |
| Guide tones, ♭3 and ♭7 | F3 C4 | 7 st, 96 mm | subset | omits D and A♭ |
| Rootless close | F3 A♭3 C4 | 7 st, 96 mm | subset | omits D |

## Diatonic function by key

| Key | Roman numeral | Function |
| --- | --- | --- |
| C minor | iim7♭5 | Predominant |
| E♭ major | viim7♭5 | Dominant function |

Classification system: common-practice functional harmony.

## Progressions (2)

| Progression | Key | Role | Sequence | Voice leading |
| --- | --- | --- | --- | --- |
| ii, v, i | C minor | iim7♭5 | Dm7♭5 to Gm7 to Cm7 | Dm7♭5 opens the phrase |
| vii, I | E♭ major | viim7♭5 | Dm7♭5 to E♭maj7 | Dm7♭5 opens the phrase |

## One-edit neighbors

| Becomes | Edit | Changes | Common tones |
| --- | --- | --- | --- |
| Ddim | 1 ♭3 ♭5 | drops C | 3 |
| Dm7 | 1 ♭3 5 ♭7 | A♭ becomes A | 3 |
| Ddim7 | 1 ♭3 ♭5 ♭♭7 | C becomes C♭ | 3 |
| Dm9 | 1 ♭3 5 ♭7 9 | A♭ becomes A, E | 3 |
| Dm | 1 ♭3 5 | A♭, C becomes A | 2 |
| D7 | 1 3 5 ♭7 | F, A♭ becomes F♯, A | 2 |
| DmMaj7 | 1 ♭3 5 7 | A♭, C becomes A, C♯ | 2 |
| Daug7 | 1 3 ♯5 ♭7 | F, A♭ becomes F♯, A♯ | 2 |
| D7sus4 | 1 4 5 ♭7 | F, A♭ becomes G, A | 2 |
| Dm6 | 1 ♭3 5 6 | A♭, C becomes A, B | 2 |

## Set theory

- Absolute pitch classes: {2, 5, 8, 0}
- Relative pitch classes: [0, 3, 6, 10]
- Normal order: [0, 2, 5, 8]
- Prime form: (0258)
- Forte number: 4-27
- Interval vector: <012111>

## Frequencies (close root position)

| Note | MIDI | Frequency |
| --- | --- | --- |
| D3 | 50 | 146.83 Hz |
| F3 | 53 | 174.61 Hz |
| A♭3 | 56 | 207.65 Hz |
| C4 | 60 | 261.63 Hz |

## Questions and answers

### What notes are in Dm7♭5?

Dm7♭5 contains D, F, A♭ and C. The formula is 1, ♭3, ♭5, ♭7.

### How do you play Dm7♭5 on piano?

Play D, F, A♭ and C together. Right hand fingers 1, 2, 3, 5; left hand 5, 3, 2, 1. A♭ is a black key; D, F and C are white.

### What are the inversions of Dm7♭5?

4 positions: root position D F A♭ C, Dm7♭5/F, Dm7♭5/A♭, Dm7♭5/C.

### What keys contain Dm7♭5?

2: iim7♭5 in C minor, viim7♭5 in E♭ major.

### What is the difference between Dm7♭5 and Ddim?

Drops C. 3 of the notes are shared.

### What is an easy Dm7♭5 for small hands?

The guide tones, ♭3 and ♭7 voicing, F3 C4, spans 7 semitones or about 96 mm.

### What are the frequencies of Dm7♭5?

From D3 at A440 in 12-TET: 146.83, 174.61, 207.65, 261.63 Hz.

### What is the set class of Dm7♭5?

Prime form (0258), Forte 4-27, interval vector &lt;012111&gt;.

### How do I transpose Dm7♭5 to another key?

Keep the 1, ♭3, ♭5, ♭7 formula on the new root. Cm7♭5 is C, E♭, G♭, B♭; C♯m7♭5 is C♯, E, G, B.

## Provenance

Every derived value above is computed by the piano.org theory kernel from the root, the quality and the stated parameters. Nothing is hand-entered per chord.

Machine record: https://piano.org/api/knowledge/v1/entities/chord:half-diminished-7th:d
Last reviewed: 2026-08-12