Convert Mechanical Horsepower to Watts
Convert Mechanical Horsepower (hp) to Watts (W) instantly and accurately.
Conversion Formula
W = hp × 745.6998716
About Mechanical Horsepower
The mechanical horsepower (hp) is exactly 550 ft·lbf/s ≈ 745.7 W - defined by James Watt by timing mine horses to set a comparable steam engine rating. A typical compact car produces 100-150 hp (75-112 kW); a sports car 300-600 hp; an F1 car ~1,000 hp (745 kW). SAE net horsepower is measured at the flywheel with all accessories fitted. Marine diesel engines, aircraft piston engines, and lawn equipment are still rated in hp. 1 hp = 550 ft·lbf/s = 745.6998715822704 W.
About Watts
The watt (W) is the SI unit of power - 1 J/s - named after James Watt (1736-1819). Familiar power levels: smartphone charging 5-65 W; laptop 15-100 W; microwave 700-1,200 W; electric kettle 2,000-3,000 W; human resting metabolism ~80 W; peak sprint ~2,000 W. The now-obsolete 100 W incandescent bulb is replaced by a 10-15 W LED producing the same light. In AC circuits, reactive power uses the var and apparent power the VA, both derived from watts. 1 W = 1 J/s = 1 kg·m²/s³.
Quick Reference Table
| Mechanical Horsepower (hp) | Watts (W) |
|---|---|
| 1 hp | 745.7 W |
| 2 hp | 1491.4 W |
| 5 hp | 3728.5 W |
| 10 hp | 7457 W |
| 25 hp | 18642.5 W |
| 50 hp | 37285 W |
| 100 hp | 74570 W |