C Diminished Triad

Chord Tones: C Diminished Triad

Symbol: dim, ° — Formula: 1-♭3-♭5

DegreeNoteFrequency (A=440, Equal)
1 C 261.626 Hz
♭3 D# 311.127 Hz
♭5 F# 369.994 Hz

Chord Notation

Notation TypeSymbol / Value
Lead Sheet SymbolCdim
All Common Symbolsdim, °
Interval Formula1-♭3-♭5
Harmonic Categorydissonant

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 C D# F# C C Diminished Triad
First Inversion D# F# C D# C Diminished Triad/D#
Second Inversion F# C D# F# C Diminished Triad/F#

Harmonic Function

The C diminished chord commonly functions as the tonic (I) in C major/minor. Its harmonic role varies by key — in major keys it provides stable harmonic grounding.

The diminished triad features a flat third and flat fifth, creating a tense, unstable sound. It occurs naturally on the seventh degree of the major scale and resolves strongly to the tonic.

Common Progressions

The C Diminished Triad frequently appears in these progression patterns (shown in Roman numeral notation relative to key):

Songs Featuring the Diminished Triad

Well-known songs where the C Diminished Triad — 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
C 261.626 Hz 260.740 Hz 261.626 Hz
D# 311.127 Hz 309.026 Hz 313.951 Hz
F# 369.994 Hz 371.251 Hz 367.911 Hz

Scales Containing the C Diminished Triad

These scales include the C Diminished Triad as a diatonic or characteristic chord: