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), E (minor third), and G (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 G (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 C#dim or C#°. The ° or "dim" symbol means both the third and fifth are minor/diminished. Do not confuse with C#dim7 or C#ø (half-diminished), which include additional notes.
What are the inversions of C# Diminished?
First inversion (C# Diminished/E): E–G–C#. Second inversion (C# Diminished/G): G–C#–E. 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.