F♯ Diminished Seventh Chord

Chord Tones: F♯ Diminished Seventh Chord

Symbol: dim7, °7 — Formula: 1-♭3-♭5-𝄫7

DegreeNoteFrequency (A=440, Equal)
1 F♯4 369.994 Hz
♭3 A4 440.000 Hz
♭5 C4 261.626 Hz
𝄫7 D♯4 311.127 Hz

Chord Notation

Notation TypeSymbol / Value
Lead Sheet SymbolF♯dim7
All Common Symbolsdim7, °7
Interval Formula1-♭3-♭5-𝄫7
Harmonic Categorytense

Roman numeral (e.g. I, IV, V) and Nashville Number notation are key-dependent. See Keys pages for chord function within specific keys.

Inversions

InversionNotes (low to high)Bass NoteSlash Notation
Root Position F♯4 A4 C4 D♯4 F♯ F♯ Diminished Seventh Chord
First Inversion A4 C4 D♯4 F♯4 A F♯ Diminished Seventh Chord/A
Second Inversion C4 D♯4 F♯4 A4 C F♯ Diminished Seventh Chord/C
Third Inversion D♯4 F♯4 A4 C4 D♯ F♯ Diminished Seventh Chord/D♯

Harmonic Function

The F♯ diminished seventh chord commonly functions as the tritone substitution in C major or tonic in F♯ major. Its harmonic role varies by key — in major keys it provides extended harmonic tension.

The diminished seventh chord consists of four equally-spaced minor thirds, creating a symmetrical, highly dissonant chord. It is used as a dramatic pivot chord and in chromatic passing harmony. The F♯ Diminished Seventh Chord specifically contains 4 notes: F♯, A, C, D♯ (formula: 1-♭3-♭5-𝄫7). On piano, F#-rooted chords place the root on a black key, creating hand positions that many pianists find ergonomically comfortable for fast passages. Progressive rock, jazz fusion, and electronic music use F#-rooted chords to create unexpected harmonic shifts and chromatic modulations.

Common Progressions

The F♯ Diminished Seventh Chord frequently appears in these progression patterns (shown in Roman numeral notation relative to key):

Songs Featuring the Diminished Seventh Chord

Well-known songs where the F♯ Diminished Seventh Chord — or this chord type — plays a prominent role:

Tuning Frequencies Across Temperaments

Frequencies shown at A=440 Hz. View full temperament data for any note.

NoteEqual Temp.PythagoreanJust Intonation
F♯4 369.994 Hz 371.251 Hz 367.911 Hz
A4 440.000 Hz 440.000 Hz 436.043 Hz
C4 261.626 Hz 260.740 Hz 261.626 Hz
D♯4 311.127 Hz 309.026 Hz 313.951 Hz

Scales Containing the F♯ Diminished Seventh Chord

These scales include the F♯ Diminished Seventh Chord as a diatonic or characteristic chord: