C# Diminished
Introduction
Enharmonic equivalent: C♯ is enharmonically equivalent to D♭. See Db Diminished.
Notes
C# Diminished Inversions
| Position | Notes |
|---|---|
| Root Position | C#4 – E4 – G4 |
| 1st Inversion | E4 – G4 – C#5 |
| 2nd Inversion | G4 – C#5 – E5 |
Key Signature
The key of C# Diminished has 7 sharps: F♯, C♯, G♯, D♯, A♯, E♯, B♯.
Theory: Intervals
The C# Diminished is built by stacking intervals from the root note. The formula R-m3-d5 describes the scale degrees used. The intervals P1-m3-d5 show the distance between each note in the chord.
C# Diminished — Frequently Asked Questions
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.
Practice Tips
- Compare C# Minor and C# Diminished: only the fifth changes (G vs perfect fifth). Play both back to back — the extra compression is striking.
- The tritone between C# and G creates maximum tension — practice just this two-note interval to hear its characteristic sound.
- C# Diminished most naturally resolves up by half step: play C#dim then a chord whose root is C# raised by one semitone.
- Practice all inversions: C#–E–G, E–G–C#, G–C#–E.
- Use C# Diminished as a vii° chord: it is one semitone below C## Major — try C#dim → C## Major to feel this powerful classical resolution.
- In a major key, find where C# Diminished fits naturally as a passing chord between two diatonic chords a step apart.