What notes are in a C♯ diminished chord?

C♯ diminished contains three notes: C♯ (the root), E (the minor third), and G (the diminished fifth).

What key is C♯ diminished from?

C♯° is the vii° (leading-tone) chord of D major and the ii° chord of B minor. Both keys share the same two-sharp signature.

How does C♯ diminished resolve?

In D major, C♯° resolves to D major (I): C♯ rises to D, E falls or holds, and G drops to F♯. The voice-leading is among the strongest in tonal music.

Is C♯ diminished the same as D♭ diminished?

They'd be enharmonic in pitch, but D♭° spelling (D♭–F♭–A𝄫) requires a double-flat, so it's essentially never written. C♯° is the practical spelling for this chord.

C# diminished chord — notes, intervals, and practice

C♯ diminished is the leading-tone (vii°) chord of D major — one of the most common functional roles for any diminished triad. The chord stacks two minor thirds: C♯, E, G. Its tritone between C♯ and G generates strong pull toward D, making C♯° a textbook cadential preparation in D major.

Intervals

The C# diminished chord stacks two thirds on the root. Each interval and its size in semitones:

C#→Eminor 3rd3 semitones
E→Gminor 3rd3 semitones
C#→Gdiminished 5th6 semitones

On the keyboard

Each note of the C# diminished chord highlighted on a piano. Pitch class is what matters — any octave works.

On the guitar

One voicing of the C# diminished chord on a six-string guitar fretboard.

Common mistakes

C♯° contains C♯ and E natural; the fifth is G natural (not G♯ — that would make a C♯ minor chord). The combination of one sharp (C♯) and two naturals (E, G) is what gives C♯° its specific tritone colour. On piano the chord falls comfortably under the hand: black-white-white starting from C♯.

In context

C♯° is the vii° of D major (resolving to D) and the ii° of B minor (resolving through V = F♯ major to i = B minor). In the cadence vii° → I, the root C♯ rises to D, the third E falls or holds, and the fifth G falls to F♯ — the classic leading-tone resolution.

Drill it

The C# diminished chord is one of 48 in the Chord Trainer. Open the full trainer to practice it alongside related chords with timing and best-time tracking.

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Frequently asked

What notes are in a C♯ diminished chord?: C♯ diminished contains three notes: C♯ (the root), E (the minor third), and G (the diminished fifth).
What key is C♯ diminished from?: C♯° is the vii° (leading-tone) chord of D major and the ii° chord of B minor. Both keys share the same two-sharp signature.
How does C♯ diminished resolve?: In D major, C♯° resolves to D major (I): C♯ rises to D, E falls or holds, and G drops to F♯. The voice-leading is among the strongest in tonal music.
Is C♯ diminished the same as D♭ diminished?: They'd be enharmonic in pitch, but D♭° spelling (D♭–F♭–A𝄫) requires a double-flat, so it's essentially never written. C♯° is the practical spelling for this chord.