Metric horsepower (PS, Pferdestärke) equals approximately 735.5 watts, slightly less than imperial horsepower, and is the standard power unit for vehicle ratings throughout Europe and Asia. Car specifications in Germany, Japan, and China typically list engine output in PS. One PS equals about 0.9863 imperial horsepower or 0.7355 kilowatts.

Foot-pounds per second (ft·lbf/s) equals approximately 1.356 watts, an imperial power unit occasionally used in mechanical engineering contexts. While less common than horsepower for engine ratings, it provides a direct connection between torque and rotational speed. One foot-pound per second equals about 1.356 watts or 0.00182 horsepower.