The invention relates to a clamping device (1), for example swing tensioners (1), bracing elements, machine vises or block cylinders, with a movable clamping element (2) for clamping a workpiece with a defined clamping force, and with an electric motor (10) for mechanically driving the clamping element (2), also with a control unit that controls the electric motor (10). The invention provides that the control unit detects an electrical operating parameter of the electric motor (10) as a measure of the clamping force. The contact of the clamping element with the workpiece is detected in this manner. Subsequently, the electric motor (10) is then driven further by a defined number of revolutions, the number of revolutions after contact with the workpiece defining the clamping force. The invention further comprises a corresponding control method.