Power Converter
Convert watts, kilowatts, horsepower and BTU per hour.
Metric horsepower (PS) is a different unit, about 1.4% smaller.
1 kilowatt equals 1.34102 mechanical horsepower
About power units
Power is the rate of energy transfer: one watt is one joule per second. Horsepower is not a single unit — mechanical horsepower (745.7 W) is used in the US and UK, while metric horsepower or PS (735.5 W) is quoted in much of Europe, a difference of about 1.4%.
Power is energy transferred per time: 1 W = 1 J/s. Mechanical, metric and electrical horsepower have different definitions; select the version stated on the equipment rating.
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All units
Compare unit values in the base unit. Numbers are rounded to 8 significant digits; conventions and assumptions appear beside the units.
| Unit | Symbol | 1 unit in W |
|---|---|---|
| watt | W | 1 |
| kilowatt | kW | 1,000 |
| megawatt | MW | 1,000,000 |
| gigawatt | GW | 1,000,000,000 |
| milliwatt | mW | 0.001 |
| mechanical horsepowerMetric horsepower (PS) is a different unit, about 1.4% smaller. | hp | 745.69987 |
| metric horsepower | PS | 735.49875 |
| electrical horsepower | hp(E) | 746 |
| boiler horsepower | hp(S) | 9,809.5 |
| BTU per hour | BTU/h | 0.29307107 |
| ton of refrigeration | RT | 3,516.8528 |
| foot-pound per second | ft·lbf/s | 1.3558179 |
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