Watts to Horsepower (W to hp)
One mechanical horsepower is defined as 550 foot-pounds of work per second, which is 745.699872 watts (NIST SP 811). To turn watts into horsepower, divide by 745.7 — or multiply by 0.001341.
Formula
hp = watts ÷ 745.7
Example: 746 watts = 1.0004 horsepower.
Watts to Horsepower chart
| watts | horsepower |
|---|---|
| 100 | 0.134102 |
| 250 | 0.335256 |
| 500 | 0.670511 |
| 746 | 1.0004 |
| 750 | 1.00577 |
| 1,000 | 1.34102 |
| 1,500 | 2.01153 |
| 2,000 | 2.68204 |
| 3,000 | 4.02307 |
| 5,000 | 6.70511 |
| 7,500 | 10.0577 |
| 10,000 | 13.4102 |
| 20,000 | 26.8204 |
| 50,000 | 67.0511 |
| 100,000 | 134.102 |
Good to know
Electric motors are rated in 'electric horsepower', which is exactly 746 W, so a 746 W motor is 1 hp on its nameplate. European engines are often quoted in metric horsepower (PS or CV), which is 735.5 W — about 1.4% smaller than mechanical horsepower, so the PS figure for the same engine is always a little higher.
Power ratings on appliances are what they draw from the wall, not what they deliver. A 1,200 W blender motor is 1.6 hp of electrical input; the power reaching the blades is lower because no motor is 100% efficient.
Frequently asked questions
How many horsepower is 1,000 watts?
1,000 W (1 kW) is 1.341 hp.
How many horsepower is 750 watts?
750 W is 1.006 hp — which is why 750 W e-bike and trolling motors are marketed as '1 hp'.
How many watts is 1 hp?
745.7 W for mechanical horsepower, 746 W for electric horsepower and 735.5 W for metric horsepower (PS).