The C Diminished chord is a three-note chord made up of C, E♭, and G♭. It is built from a root, minor third, and diminished fifth.
Construction
C Diminished = Root + Minor 3rd + Diminished 5th = C · E♭ · G♭
| Note | Interval | Degree |
|---|---|---|
| C | Root | 1 |
| E♭ | Minor 3rd | ♭3 |
| G♭ | Diminished 5th | ♭5 |
C Diminished Inversions
| Position | Notes |
|---|---|
| Root Position | C – E♭ – G♭ |
| 1st Inversion | E♭ – G♭ – C |
| 2nd Inversion | G♭ – C – E♭ |
Key Signature
A Diminished chord is built from symmetrical or ambiguous intervals, so it doesn’t belong to a single key and has no key signature of its own.
How C Diminished functions in a key
The same chord takes on a different harmonic role depending on the key it appears in. Here is where C Diminished sits diatonically across the common keys:
- In D♭ major, C Diminished is the vii° chord — the dominant.
- In B♭ minor, C Diminished is the ii° chord — a predominant.
C Diminished — Frequently Asked Questions
What is the C Diminished chord on piano?
The C Diminished chord contains the notes C – E♭ – G♭. On piano, play these notes together to sound the chord.
What notes are in the C Diminished chord?
The C Diminished chord contains: C (root), Eb (minor third), and Gb (diminished fifth). Both intervals are compressed: the minor third is 3 semitones above the root, and the diminished fifth is 6 semitones — a tritone.
How does C Diminished differ from C Minor?
C Minor has a perfect fifth. C Diminished lowers the fifth by one semitone to Gb (diminished fifth). That extra compression creates intense harmonic tension — the tritone between root and diminished fifth is the most dissonant interval in Western music.
What is the symbol for the C Diminished?
C Diminished is written as Cdim or C°. The ° or "dim" symbol means both the third and fifth are minor/diminished. Do not confuse with Cdim7 or Cø (half-diminished), which include additional notes.
What are the inversions of C Diminished?
First inversion (C Diminished/Eb): Eb–Gb–C. Second inversion (C Diminished/Gb): Gb–C–Eb. Diminished triads are used in classical music as the vii° chord — the chord one semitone below the tonic, with strong resolution pull.
How is C Diminished used in music?
C Diminished most commonly functions as the vii° chord in a major key, creating strong resolution back to the tonic. It also works as a chromatic passing chord between two nearby chords, and in classical music as a brief point of dissonance. Jazz uses the full four-note dim7 more often than the triad.
What songs use diminished chords?
Michelle (Beatles) uses a diminished chord as a chromatic passing chord. Many classical pieces use vii°–I cadences. Jazz standards use dim7 chords as chromatic passing and approach chords. Diminished harmony also appears in flamenco and film music for dramatic tension.