Chäserrugg is a mountain in Wildhaus-Alt St. Johann municipality, Toggenburg, canton of St. Gallen, Switzerland, rising to 2,262 m. It is the easternmost of the "seven peaks" of the Churfirsten, the other six being, running east to west, Hinterrugg, Schibenstoll, Zuestoll, Brisi, Frümsel, Selun.