Horsepower to Watts
Mechanical horsepower, about 745.7 watts, is the traditional unit for rating car and engine power in the US and UK. The watt is the SI unit of power, equal to one joule per second, used to rate everything from light bulbs to engines. 1 hp equals ≈745.7 W, so converting between them is a matter of multiplying by that fixed factor — type any value into the converter below and both sides update instantly as you type.
Both units belong to power, measured here against power's base unit (W) — every other power unit on this site converts through that same reference point, which is why the table below can also be read as a quick cross-check against nearby values.
Formula
W = hp × ≈745.7
hp = W × ≈0.00134102
Worked example: 5 hp × ≈745.7 = ≈3,728.5 W.
Conversion table
| Horsepower (mech.) (hp) | Watt (W) |
|---|---|
| 1 hp | ≈745.7 W |
| 2 hp | ≈1,491.4 W |
| 3 hp | ≈2,237.1 W |
| 5 hp | ≈3,728.5 W |
| 10 hp | ≈7,457 W |
| 20 hp | ≈14,914 W |
| 25 hp | ≈18,642.5 W |
| 50 hp | ≈37,285 W |
| 100 hp | ≈74,570 W |
| 250 hp | ≈186,425 W |
| 500 hp | ≈372,850 W |
| 1,000 hp | ≈745,700 W |
Frequently asked
- How many Watts in a horsepower (mech.)?
- 1 hp equals ≈745.7 W.
- How do I convert Horsepower to Watts?
- Multiply the value in hp by ≈745.7 to get W. The converter above does this instantly as you type.
- Is the conversion exact?
- Yes — Horsepower (mech.) and Watt are both defined by a fixed conversion factor to power's base unit (W), so the result shown is exact to the precision displayed, not an approximation.