Conversions

Horsepower to Watts Calculator

By HowMuchWatts Editorial Team Reviewed June 30, 2026 Formula and source method

Convert mechanical horsepower into watts and kilowatts — useful for sizing motors, pumps and generators.

Change any number below — your result updates instantly, no button to click.

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Power

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Power

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Written & maintained by the HowMuchWatts team · Last updated June 30, 2026 · How we verify our numbers

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.

These calculators provide general estimates for educational purposes only and are not financial advice. Real-world results depend on factors not captured here. Verify figures independently before making any purchase or financial decision.

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