W to hp — convert watts to mechanical horsepower
Exact 1 ÷ 745.699872 = 0.00134102209
1 watt in other units
| Kilowatts | 0.001 | kW |
|---|---|---|
| Megawatts | 0.000001 | MW |
| Mechanical horsepower | 0.00134102209 | hp |
| Metric horsepower | 0.001359621617 | PS |
| BTU per hour | 3.412142 | BTU/h |
| Foot-pounds per second | 0.73756215 | ft·lbf/s |
W to hp at a glance
| Watts | Mechanical horsepower |
|---|---|
| 1 W | 0.00134102209 hp |
| 2 W | 0.002682044179 hp |
| 3 W | 0.004023066269 hp |
| 5 W | 0.006705110448 hp |
| 10 W | 0.01341022 hp |
| 20 W | 0.02682044 hp |
| 25 W | 0.03352555 hp |
| 50 W | 0.0670511 hp |
| 100 W | 0.13410221 hp |
| 250 W | 0.33525552 hp |
| 500 W | 0.67051104 hp |
| 1,000 W | 1.341022 hp |
How to convert watts to mechanical horsepower
Multiply by 0.00134102209 — one watt is 0.00134102209 mechanical horsepower. That factor is exact: it comes from the definition of the units rather than from a measurement, so it will not change and does not need rounding.
Working 1 ÷ 745.699872 = 0.00134102209
Questions
How many mechanical horsepower are in a watt?
One watt is 0.00134102209 mechanical horsepower. This figure is exact — it comes from the definition of the unit, not a measurement.
What is 1 watt in mechanical horsepower?
1 watt is 0.00134102209 mechanical horsepower. The working is 1 ÷ 745.699872 = 0.00134102209.
Why does the same car have two different horsepower figures?
Because there are two horsepowers. Metric horsepower, written PS or CV, is 735.49875 W; mechanical horsepower, written hp or bhp, is about 745.7 W. A car sold as 150 PS in Germany is 148 hp in Britain, and nothing about the engine has changed.
Where does 746 watts come from?
From James Watt, who needed to sell steam engines to people who owned horses. He measured a mill horse turning a wheel and settled on 550 foot-pounds per second — a figure most real horses cannot sustain, which made the comparison flattering to his engines.
How do I read an air conditioner's BTU rating?
BTU ratings are BTU per hour, a rate of heat movement, even when the "per hour" is dropped. A 12,000 BTU/h unit shifts about 3.5 kW of heat. That is not what it draws from the wall — a decent unit moves several times more heat than the electricity it consumes.
What is the difference between power and energy?
Power is a rate, energy is an amount. A kilowatt is how fast something uses energy; a kilowatt-hour is how much it used. A 2 kW heater running for three hours has a power of 2 kW throughout and has consumed 6 kWh. Bills are in energy; ratings are in power.