Electric Motor Unit Converters

Handy unit converters for electric motor engineers and designers. Convert torque, speed, power, energy, and temperature, all in one place.

Motor datasheets rarely use the same units twice. A supplier quotes torque in Nm, a customer asks for lbf-ft, and a control board's firmware wants rad/s instead of RPM. These six converters cover the unit pairs that come up most often when specifying, comparing, or documenting an electric motor.

The power, torque and speed converter ties the three together with the standard motor equation, useful when a datasheet gives two of the three values and you need the third. The angular speed converter switches between RPM, the unit most datasheets use, and rad/s, the unit most control equations expect. The torque converter handles Newton-meters and pound-feet, the two units that show up interchangeably depending on whether a supplier is European or American. The horsepower to watts converter bridges an older unit still common in pump and compressor specifications with the SI unit used everywhere else. The energy converter moves between joules and kilowatt-hours, useful when comparing a motor's instantaneous rating against a battery's stored energy. The temperature converter handles Celsius and Fahrenheit, needed whenever a winding temperature limit is quoted in a unit your test equipment does not use.