C-sharp major

C-sharp major
${ \magnifyStaff #3/2 \omit Score.TimeSignature \key cis \major s16 \clef F \key cis \major s^"" }$
Relative key	A-sharp minor
Parallel key	C-sharp minor
Dominant key	G-sharp major (theoretical); →enharmonic : A-flat major
Subdominant key	F-sharp major
Enharmonic key	D-flat major
Component pitches
	C♯, D♯, E♯, F♯, G♯, A♯, B♯

C-sharp major is a major scale based on C♯, consisting of the pitches C♯, D♯, E♯, F♯, G♯, A♯, and B♯. Its key signature has seven sharps. Its relative minor is A-sharp minor (or enharmonically B-flat minor), its parallel minor is C-sharp minor, and its enharmonic equivalence is D-flat major.

The C-sharp major scale is:

$\header { tagline = ##f } scale = \relative b { \key cis \major \omit Score.TimeSignature cis^"C♯ natural major scale" dis eis fis gis ais bis cis bis ais gis fis eis dis cis2 \clef F \key cis \major } \score { { << \cadenzaOn \scale \context NoteNames \scale >> } \layout { } \midi { } }$

Changes needed for the melodic and harmonic versions of the scale are written in with accidentals as necessary. The C-sharp harmonic major and melodic major scales are:

$\header { tagline = ##f } scale = \relative b { \key cis \major \omit Score.TimeSignature cis^"C♯ harmonic major scale" dis eis fis gis a bis cis bis a gis fis eis dis cis2 \clef F \key cis \major } \score { { << \cadenzaOn \scale \context NoteNames \scale >> } \layout { } \midi { } }$

$\header { tagline = ##f } scale = \relative b { \key cis \major \omit Score.TimeSignature cis^"C♯ melodic major scale (ascending and descending)" dis eis fis gis ais bis cis b a gis fis eis dis cis2 \clef F \key cis \major } \score { { << \cadenzaOn \scale \context NoteNames \scale >> } \layout { } \midi { } }$

A harp tuned to C-sharp major has all its pedals in the bottom position. Because all the strings are then pinched and shortened, this is the least resonant key for the instrument.