C♯ (musical note)

C♯ (musical note)

C (C-sharp) is a musical note lying a chromatic semitone above C and a diatonic semitone below D. C sharp is thus enharmonic to D (D). It is the second semitone in the French solfege and is known there as Do Dièse.

When calculated in equal temperament with a reference of A above middle C as 440 Hz, the frequency of C4 (the C above middle C) is about 277.18 Hz. See pitch (music) for a discussion of historical variations in frequency.

See also