How to Convert Horsepower to Kilowatts (hp to kW)
Power conversions help compare car engines in hp and kW, and air-con units rated in BTU/h against their electrical draw in watts. This guide shows how to convert horsepower into kilowatts by hand, with examples and a quick-reference table.
The conversion
To convert horsepower to kilowatts, multiply the value by 0.745699872. To go the other way, divide by the same number (or multiply by 1.3410220888). For a quick estimate, multiply by about 0.75.
Kilowatts = horsepower × 0.745699872
Worked examples
- 3 hp = 2.2371 kW
- 12.5 hp = 9.3212 kW
- 75 hp = 55.9275 kW
Horsepower to Kilowatts table
| Horsepower | Kilowatts |
|---|---|
| 1 hp | 0.7457 kW |
| 2 hp | 1.4914 kW |
| 5 hp | 3.7285 kW |
| 10 hp | 7.457 kW |
| 20 hp | 14.914 kW |
| 25 hp | 18.6425 kW |
| 50 hp | 37.285 kW |
| 100 hp | 74.57 kW |
| 250 hp | 186.425 kW |
| 500 hp | 372.8499 kW |
| 1,000 hp | 745.6999 kW |
Common questions
Is hp to kW exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Kilowatts to Horsepower converter.
Mistakes to avoid
Mixing similar-sounding units
US and imperial gallons, pints and tons are different sizes, and decimal kilobytes differ from binary kibibytes.
Forgetting squared and cubed units
Area and volume factors are the length factor squared or cubed, so 1 m² is about 10.76 sq ft, not 3.28.
Multiplying when you should divide
Converting to a smaller unit gives a bigger number, and converting to a larger unit gives a smaller one. If your answer moves the wrong way, you have inverted the factor.
Background
A conversion table is handy for common values, but a calculator is faster and avoids interpolation errors for anything in between.
Singapore adopted the metric system in the 1970s, replacing imperial units and traditional Chinese measures in most official uses. Metric units are now standard in schools, trade and government, but older units survive in property, markets and imported goods.
For everyday use, three or four significant figures are usually enough. Engineering, science and trade documents may need more, and rounding should happen only at the end of a calculation.
For any value, use the Horsepower to Kilowatts Converter or browse all power converters.
Run your own numbers: Horsepower to Kilowatts Converter