# D Diminished 7th piano chord (Ddim7) Ddim7 contains D, F, A♭ and C♭. Three stacked minor thirds. A♭ is a black key; D, F and C♭ are white. - Canonical page: https://piano.org/chords/diminished-7th/d/ - Entity: chord:diminished-7th:d - Notes: D F A♭ C♭ - Formula: 1 ♭3 ♭5 ♭♭7 - Intervals from root: P1, m3, TT, M6 - Interval stack (semitones): 3 3 3 - Also written: Ddim7, Ddim7, D 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♭ | Major sixth | 9 | ## 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 C♭3 | 7 | 9 st, 124 mm | | First inversion (Ddim7/F) | F | F3 A♭3 C♭3 D4 | 6/5 | 9 st, 124 mm | | Second inversion (Ddim7/A♭) | A♭ | A♭3 C♭3 D4 F4 | 4/3 | 9 st, 124 mm | | Third inversion (Ddim7/C♭) | C♭ | C♭3 D4 F4 A♭4 | 4/2 | 9 st, 124 mm | ## Voicings (10) | Voicing | Notes | Span | Relation | Omits or adds | | --- | --- | --- | --- | --- | | Close, root position | D3 F3 A♭3 C♭3 | 9 st, 124 mm | identical | none | | Close, first inversion | F3 A♭3 C♭3 D4 | 9 st, 124 mm | identical | none | | Close, second inversion | A♭3 C♭3 D4 F4 | 9 st, 124 mm | identical | none | | Close, third inversion | C♭3 D4 F4 A♭4 | 9 st, 124 mm | identical | none | | Drop 2 | A♭2 D3 F3 C♭3 | 15 st, 206 mm | identical | none | | Drop 3 | F2 D3 A♭3 C♭3 | 18 st, 248 mm | identical | none | | Drop 2 and 4 | D2 A♭2 F3 C♭3 | 21 st, 289 mm | identical | none | | Shell, root ♭♭7 ♭3 | D2 C♭2 F3 | 15 st, 206 mm | subset | omits A♭ | | Guide tones, ♭3 and ♭♭7 | F3 C♭3 | 6 st, 83 mm | subset | omits D and A♭ | | Rootless close | F3 A♭3 C♭3 | 6 st, 83 mm | subset | omits D | ## One-edit neighbors | Becomes | Edit | Changes | Common tones | | --- | --- | --- | --- | | Ddim | 1 ♭3 ♭5 | drops C♭ | 3 | | Dm7♭5 | 1 ♭3 ♭5 ♭7 | C♭ becomes C | 3 | | Dm6 | 1 ♭3 5 6 | A♭ becomes A | 3 | | Dm | 1 ♭3 5 | A♭, C♭ becomes A | 2 | | Dm7 | 1 ♭3 5 ♭7 | A♭, C♭ becomes A, C | 2 | | DmMaj7 | 1 ♭3 5 7 | A♭, C♭ becomes A, C♯ | 2 | | D6 | 1 3 5 6 | F, A♭ becomes F♯, A | 2 | ## Set theory - Absolute pitch classes: {2, 5, 8, 11} - Relative pitch classes: [0, 3, 6, 9] - Normal order: [2, 5, 8, 11] - Prime form: (0369) - Forte number: 4-28 - Interval vector: <004002> ## Frequencies (close root position) | Note | MIDI | Frequency | | --- | --- | --- | | D3 | 50 | 146.83 Hz | | F3 | 53 | 174.61 Hz | | A♭3 | 56 | 207.65 Hz | | C♭3 | 59 | 246.94 Hz | ## Questions and answers ### What notes are in Ddim7? Ddim7 contains D, F, A♭ and C♭. The formula is 1, ♭3, ♭5, ♭♭7. ### How do you play Ddim7 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 Ddim7? 4 positions: root position D F A♭ C♭, Ddim7/F, Ddim7/A♭, Ddim7/C♭. ### What is the difference between Ddim7 and Ddim? Drops C♭. 3 of the notes are shared. ### What is an easy Ddim7 for small hands? The guide tones, ♭3 and ♭♭7 voicing, F3 C♭3, spans 6 semitones or about 83 mm. ### What are the frequencies of Ddim7? From D3 at A440 in 12-TET: 146.83, 174.61, 207.65, 246.94 Hz. ### What is the set class of Ddim7? Prime form (0369), Forte 4-28, interval vector <004002>. ### How do I transpose Ddim7 to another key? Keep the 1, ♭3, ♭5, ♭♭7 formula on the new root. C♯dim7 is C♯, E, G, B♭; D♯dim7 is D♯, F♯, A, C. ## 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:diminished-7th:d Last reviewed: 2026-08-12