The necessity of a measurement of the torque exists in many car test stands. In a number of stands as the load for a engine the electrical machines are used. The torque of electrical machines is often measured approximately regarding the input current. Sometimes more complex estimations are applied, taking into account the field current for dc machines or a slip for ac machines. In the paper presented the opportunities of more exact measurement of the torque using information on current, voltage and shaft rotation frequency are analyzed.