Torque is a significant measurement in a range of applications, including gas turbines with e.g. 50 kN·m of nominal torque at 8000 min–1 and a mechanical output of over 40 MW, or Formula 1 test benches with nominal torque in the range up to 2 kN·m with speeds of > 20,000 min–1. Torque is an important measurement almost everything, including the screw caps on medicine bottles, and for many products the permitted tolerances are mandatory. The automotive industry is faced with consumer demand for vehicles that offer lower fuel consumption, greater operating safety, longer-lasting reliability, and higher levels of comfort. This demand and even stricter legal requirements for lower emissions has resulted in a need for metrological and test techniques. The data required now needs to be acquired precisely and reproducibly, and torque is one of the critical measurements, especially for the development of combustion engines and transmission. This also affecting the increasing testing in e-mobility. In combination with rotation speed, this enables mechanical power to be calculated. Previously for engine test benches, measurement was fulfilled by using braking devices with a measurement capability, but now it is more common to perform in-line torque measurement using rotating torque transducers. The use of rotating torque transducers is more common as the processes are dynamic, and the interplay between mechanisms is an increasingly important consideration for optimization.