Sus4 chords

A sus4 chord is a 3-note chord — the root plus a perfect fourth and a perfect fifth above it. The third is dropped and the fourth stands in its place, leaving the chord neither major nor minor.

It sounds taut and unresolved, leaning hard toward the plain major chord. Below are the sus4 chords for all twelve keys, from C to B — pick any chart for its full set of voicings, the piano shape and how it's built.