Horsepower to Watts Calculator
Convert mechanical horsepower into watts and kilowatts — useful for sizing motors, pumps and generators.
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Results
Last updated June 30, 2026. Results update automatically as you type.
How it works
Watts = horsepower × 745.7. Kilowatts = watts ÷ 1000. (This uses mechanical/motor horsepower; metric horsepower is slightly different at 735.5 W.)
Frequently asked questions
How many watts is 1 horsepower?
About 745.7 watts (0.746 kW) for mechanical horsepower.
Is this the electricity a motor uses?
It is the output power. A real motor draws somewhat more electrical power because it is not 100% efficient — divide by its efficiency for input watts.
Mechanical vs metric horsepower?
Mechanical (used here) is 745.7 W; metric horsepower is 735.5 W. The difference is small but matters for precise work.
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