What is the horsepower rating of an electric motor?

Answer 1

Horsepower is the Imperial unit of measurement for power. In North America, the horsepower is still used to define the rated output power of a motor, whereas the watt is used to define its corresponding input power. Because no device is 100% efficient, a motor's rated output power is always lower than its corresponding input power.

Elsewhere in the world, horsepower is considered to be an obsolete unit of measurement and, so, the watt is used to define both the rated output power and the corresponding input power.

Answer 2

A motor is driving something, like a pump, compressor, fan, winch, etc. In the United States, it is common to use horsepower as a reference unit for the amount of power necessary to drive the device. 1 horsepower is equal to approximately 746 watts.

Comment

This is only true in North America. Practically everywhere else in the world, the horsepower is now considered obsolete, and the watt is used.