All conversions
| Unit | Value | Copy |
|---|---|---|
| Milliwatt (mW) | — | |
| Watt (W) | — | |
| Kilowatt (kW) | — | |
| Megawatt (MW) | — | |
| Horsepower (mechanical) (hp) | — | |
| Horsepower (metric, PS) (PS) | — | |
| BTU per hour (BTU/h) | — | |
| Kilocalorie per hour (kcal/h) | — | |
| Foot-pound per second (ft·lbf/s) | — | |
| Ton of refrigeration (TR) | — |
Convert engine output, appliance ratings and heating or cooling capacity between electrical, mechanical and thermal power units.
How to use the Power Converter
- 1 Type a value in either box — the conversion works in both directions.
- 2 Choose the units to convert power from and to, or click any row in the table.
- 3 Use the swap button to reverse the conversion, then copy the result.
Formula
1 hp (mechanical) = 745.6999 W 1 PS (metric hp) = 735.49875 W 1 BTU/h = 0.29307 W
Worked examples
Input: 150 hp
Result: 111.85 kW
Input: 12,000 BTU/h
Result: 3.517 kW
"One ton" of cooling
Power vs. energy
Power is the rate of using energy. A 2 kW heater running for 3 hours uses 6 kWh of energy. Use the Energy Converter for kWh, joules and calories.
Which horsepower?
Mechanical (imperial) horsepower — 745.7 W — is used in the US and UK. Metric horsepower (PS, CV, pk) — 735.5 W — is common in continental Europe and Asia. The difference is about 1.4%.
Frequently asked questions
How many watts is one horsepower?
About 745.7 W for mechanical horsepower, or 735.5 W for metric horsepower.
How many kW is 100 hp?
About 74.57 kW.
What does BTU/h measure?
Heating or cooling capacity, common for air conditioners and furnaces in North America.
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