Triads

C♯ diminished chord

Tense and unstable — it usually wants to resolve up by a half step.

C♯dim is the vii° chord in D major. In minor keys: ii° in B minor.

Spell as D♭dim

How to play C♯dim

x42020 · Open position

Right hand: C♯ (1), E (3), G (5)

0404 · Open position

On guitar, C♯dim has an open-position shape, x42020, using three fingers alongside the open strings. Don’t strum the low E string.

On piano, C♯dim has one black key (C♯) and two white keys.

On ukulele the usual C♯dim shape is 0404, using two fingers.

Move a single note and C♯dim becomes a different chord: raise G to G♯ for C♯m, add B for C♯m7♭5 and add B♭ for C♯dim7.