1. An input device comprising: a position detection sensor configured to detect respective positions of multiple pressing points on an operation face that are simultaneously pressed; a load detection sensor configured to detect a position of a barycenter of the multiple pressing points and a load on the barycenter; and a controller configured to calculate respective loads on the multiple pressing points based on coordinates of the positions of the multiple pressing points, coordinates of the position of the barycenter, and the load on the barycenter, wherein the controller is further configured to determine whether or not three pressing points that are simultaneously pressed are all on a same straight line, and if simultaneously-pressed three pressing points are all on the same straight line, the controller corrects the coordinates of the position of one of the pressing points and the coordinates of the position of the barycenter so as to calculate the respective loads on the pressing points.