The invention relates to a measuring device (20) for ascertaining a torque acting on an axis (A2,) and to a robot (1) with a robot arm (2) having a plurality of members which are rotatably mounted in reference to axes (A1-A6). The robot (1) also has the measuring device (20), in order to determine for at least one of the axes (A2) the torque exerted on that axis (A2).