How many watts is one horsepower?

One mechanical (imperial) horsepower equals 745.6999 watts exactly, defined as 550 foot-pounds-force per second. So a 100 hp engine is about 74,570 W or 74.57 kW.

Which horsepower does this use?

It uses mechanical (imperial) horsepower, the standard for engines and motors in the US and UK. Metric horsepower (PS) is slightly different at 735.5 W and is not used here.

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Horsepower to Watts Converter

Horsepower to watts — the exact conversion

One mechanical horsepower equals 745.6999 watts. This converter turns horsepower (hp) into watts (W) and back, using the precise definition of 745.69987158 W per horsepower (550 ft·lbf/s).

Mechanical horsepower is the figure quoted for car engines, pumps and motors in the US and UK. To get kilowatts, simply divide the watt result by 1000 — for example, 200 hp is about 149,140 W, or 149.14 kW.

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