How to convert horsepower to watts
Formula: W = hp × 745.7
Worked example: 200 hp → 200 × 745.7 = 149,140 W
One mechanical horsepower is 745.7 watts. A 1/2 hp garbage disposal or pump motor therefore produces about 373 W of mechanical power and draws somewhat more from the outlet.
Horsepower to watts conversion chart
| Horsepower (hp) | Watts (W) |
|---|---|
| 1 hp | 745.7 W |
| 5 hp | 3,728.5 W |
| 10 hp | 7,457 W |
| 50 hp | 37,285 W |
| 75 hp | 55,927.5 W |
| 100 hp | 74,570 W |
| 150 hp | 111,855 W |
| 200 hp | 149,140 W |
| 250 hp | 186,425 W |
| 300 hp | 223,710 W |
| 400 hp | 298,280 W |
| 500 hp | 372,850 W |
| 600 hp | 447,420 W |
| 800 hp | 596,560 W |
| 1,000 hp | 745,700 W |
What is one horsepower?
Mechanical horsepower, defined as 550 foot-pounds per second, equals about 745.7 watts. It is the unit of US and UK car engines, lawn mowers and boat motors. The word stays the same in the plural.
What is a watt?
The watt is the SI unit of power: one joule of energy per second. Light bulbs, chargers and small appliances are rated in watts; an LED bulb draws about 9 W and a hair dryer up to 1,800 W.