Power
Watts, kilowatts and horsepower.
About Power
Convert power between watts, kilowatts, megawatts, metric and imperial horsepower and foot-pounds per second. Every other unit is shown as you type.
How to use
- Type a value and pick its unit. The default is 1 kilowatt.
- Every other unit updates as you type; each row has its own Copy button, and Copy on the panel copies the whole table.
- Results are rounded to eight decimal places and formatted for your locale.
Conversion factors
All units convert through watts:
| Unit | Watts |
|---|---|
| kilowatt | 1 000 |
| megawatt | 1 000 000 |
| horsepower (metric, PS) | 735.49875 |
| horsepower (imperial, mechanical) | 745.69987158 |
| foot-pound per second | 1.35581794833 |
Both horsepower definitions are listed because car makers use them interchangeably; the metric figure is about 1.4% smaller. The value must be greater than zero.
Example
1 kW → 1 000 W · 1.35962162 hp (metric) · 1.34102209 hp (imperial) · 737.56214928 ft-lb/s
Privacy
Runs in the browser. No request is made, and nothing is stored.
Frequently asked questions
- How many watts is one horsepower?
- Imperial (mechanical) horsepower is 745.7 watts, defined as 550 foot-pounds per second. Metric horsepower (PS, CV) is 735.5 watts, defined as 75 kilogram-force metres per second.
- What is the difference between metric and imperial horsepower?
- Metric horsepower is about 1.4% smaller: 100 PS is 98.6 imperial hp, or 73.5 kW. European car brochures usually quote PS, while US and UK figures are usually mechanical hp.
- How do I convert kW to hp?
- Multiply by 1.341 for imperial horsepower or 1.36 for metric. A 150 kW engine is about 201 hp or 204 PS.