guitar chord
C♯sus4
The third replaced by the fourth, which leans on the third it is standing in for.
Written the other way round it is D♭sus4 — the same twelve keys on a piano, a different piece of notation.
Every fingering that fits a hand
99bb99
moderate · barre
x44674
moderate · barre
x4412x
hard
9bbb99
hard · barre
99bb9x
moderate · barre
What is true of it
C♯sus4 is C♯, F♯ and G♯ — 1, 4 and 5 counted from C♯.
These are also the notes of F♯sus2/C♯ and G♭sus2/C♯. Which name is right depends on what is underneath and what came before — the notes alone do not decide.
The easiest of the 5 fingerings below is 99bb99: 3 fingers, one of them barring the 9th fret, held at the 9th fret.
None of them uses an open string, so this chord moves up the neck unchanged — the same shape 1 fret higher is the chord a semitone above.
4 of the 5 need a barre.
Where its notes are on the neck
The brass dots are C♯, the root. Everything else is a chord tone with its degree printed in it.
With a different note underneath
C♯sus4/F♯
xx4122
C♯sus4/G♯
444674
An inversion is the same chord with a different note lowest. The name changes to a slash name because the bass is what a listener hears as the foundation.