# F Diminished piano chord (Fdim) Fdim contains F, A♭ and C♭. Two stacked minor thirds. A♭ is a black key; F and C♭ are white. - Canonical page: https://piano.org/chords/diminished/f/ - Entity: chord:diminished:f - Notes: F A♭ C♭ - Formula: 1 ♭3 ♭5 - Intervals from root: P1, m3, TT - Interval stack (semitones): 3 3 - Also written: Fdim, Fdim, F diminished - Parameters: A440, 12-TET, 165 mm octave, spans centre to centre ## Construction | Degree | Note | Interval from root | Semitones | | --- | --- | --- | --- | | 1 | F | Perfect unison | 0 | | ♭3 | A♭ | Minor third | 3 | | ♭5 | C♭ | Tritone | 6 | ## Fingering Rest your right hand over the notes with finger 1 on F, finger 3 on A♭, finger 5 on C♭. The left hand mirrors it. Right hand 1-3-5, left hand 5-3-1. Source: piano.org fingering method v1. ## Inversions | Position | Bass | Notes in order | Figured bass | Span | | --- | --- | --- | --- | --- | | Root position | F | F3 A♭3 C♭3 | 5/3 | 6 st, 83 mm | | First inversion (Fdim/A♭) | A♭ | A♭3 C♭3 F4 | 6/3 | 9 st, 124 mm | | Second inversion (Fdim/C♭) | C♭ | C♭3 F4 A♭4 | 6/4 | 9 st, 124 mm | ## Voicings (5) | Voicing | Notes | Span | Relation | Omits or adds | | --- | --- | --- | --- | --- | | Close, root position | F3 A♭3 C♭3 | 6 st, 83 mm | identical | none | | Close, first inversion | A♭3 C♭3 F4 | 9 st, 124 mm | identical | none | | Close, second inversion | C♭3 F4 A♭4 | 9 st, 124 mm | identical | none | | Open, fifth on top | F2 C♭2 A♭3 | 15 st, 206 mm | identical | none | | Root and third only | F3 A♭3 | 3 st, 41 mm | subset | omits C♭ | ## Diatonic function by key | Key | Roman numeral | Function | | --- | --- | --- | | E♭ minor | ii° | Predominant | | G♭ major | vii° | Dominant function | Classification system: common-practice functional harmony. ## Progressions (2) | Progression | Key | Role | Sequence | Voice leading | | --- | --- | --- | --- | --- | | ii°, v, i | E♭ minor | ii° | Fdim to B♭m to E♭m | Fdim opens the phrase | | vii°, I | G♭ major | vii° | Fdim to G♭ | Fdim opens the phrase | ## One-edit neighbors | Becomes | Edit | Changes | Common tones | | --- | --- | --- | --- | | Fm7♭5 | 1 ♭3 ♭5 ♭7 | adds E♭ | 3 | | Fdim7 | 1 ♭3 ♭5 ♭♭7 | adds E♭♭ | 3 | | Fm | 1 ♭3 5 | C♭ becomes C | 2 | | Fm7 | 1 ♭3 5 ♭7 | C♭ becomes C, E♭ | 2 | | FmMaj7 | 1 ♭3 5 7 | C♭ becomes C, E | 2 | | Fm6 | 1 ♭3 5 6 | C♭ becomes C, D | 2 | | F | 1 3 5 | A♭, C♭ becomes A, C | 1 | | Faug | 1 3 ♯5 | A♭, C♭ becomes A, C♯ | 1 | | Fsus2 | 1 2 5 | A♭, C♭ becomes G, C | 1 | | Fsus4 | 1 4 5 | A♭, C♭ becomes B♭, C | 1 | ## Set theory - Absolute pitch classes: {5, 8, 11} - Relative pitch classes: [0, 3, 6] - Normal order: [5, 8, 11] - Prime form: (036) - Forte number: 3-10 - Interval vector: <002001> ## Frequencies (close root position) | Note | MIDI | Frequency | | --- | --- | --- | | F3 | 53 | 174.61 Hz | | A♭3 | 56 | 207.65 Hz | | C♭3 | 59 | 246.94 Hz | ## Questions and answers ### What notes are in Fdim? Fdim contains F, A♭ and C♭. The formula is 1, ♭3, ♭5. ### How do you play Fdim on piano? Play F, A♭ and C♭ together. Right hand fingers 1, 3, 5; left hand 5, 3, 1. A♭ is a black key; F and C♭ are white. ### What are the inversions of Fdim? 3 positions: root position F A♭ C♭, Fdim/A♭, Fdim/C♭. ### What keys contain Fdim? 2: ii° in E♭ minor, vii° in G♭ major. ### What is the difference between Fdim and Fm7♭5? Adds E♭. 3 of the notes are shared. ### What is an easy Fdim for small hands? The root and third only voicing, F3 A♭3, spans 3 semitones or about 41 mm. ### What are the frequencies of Fdim? From F3 at A440 in 12-TET: 174.61, 207.65, 246.94 Hz. ### What is the set class of Fdim? Prime form (036), Forte 3-10, interval vector <002001>. ### How do I transpose Fdim to another key? Keep the 1, ♭3, ♭5 formula on the new root. Cdim is C, E♭, G♭; C♯dim is C♯, E, G. ## 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:f Last reviewed: 2026-08-12