Horsepower (mechanical) (hp)
Exactly 550 foot-pounds-force per second (about 745.69987 watts).
What is a horsepower?
- Symbol
- hp
- Quantity
- Power
- Unit system
- US customary
- Definition
- Exactly 550 foot-pounds-force per second (about 745.69987 watts).
- Exact
- Yes, the value is exact by definition
- Source
- NIST Special Publication 811 (2008), Appendix B.8
Common applications
The mechanical (imperial) horsepower used for car and engine ratings in the United States and United Kingdom.
Horsepower (mechanical) in other power units
- 1 hp = 745699.87158227022 mWMilliwatt
- 1 hp = 745.69987158227022 WHorsepower (mechanical) to Watt converter
- 1 hp = 0.74569987158227022 kWHorsepower (mechanical) to Kilowatt converter
- 1 hp = 0.00074569987158227022 MWMegawatt
- 1 hp = 7.4569987158227022e-7 GWGigawatt
- 1 hp = 1.013869665424 PSHorsepower (mechanical) to Horsepower (metric) converter
- 1 hp ≈ 2544.433578 BTU/hBTU (IT) per hour
- 1 hp = 550 ft·lbf/sFoot-pound-force per second
Horsepower (mechanical) quick reference
| Horsepower (mechanical) | Watt | Kilowatt | Horsepower (metric) |
|---|---|---|---|
| 1 hp | = 745.69987158227022 W | = 0.74569987158227022 kW | = 1.013869665424 PS |
| 10 hp | = 7456.9987158227022 W | = 7.4569987158227022 kW | = 10.13869665424 PS |
| 100 hp | = 74569.987158227022 W | = 74.569987158227022 kW | = 101.3869665424 PS |
| 1000 hp | = 745699.87158227022 W | = 745.69987158227022 kW | = 1013.869665424 PS |
Where the horsepower fits
The next smaller power unit is the metric horsepower (PS). 1 hp = 1.013869665424 PS, and 1 PS ≈ 0.9863200706 hp.
The next larger power unit is the kilowatt (kW). 1 hp = 0.74569987158227022 kW, and 1 kW ≈ 1.34102209 hp.
Frequently asked questions
- How many watts are in one horsepower?
- One horsepower = 745.69987158227022 W (watts).
- How many kilowatts are in one horsepower?
- One horsepower = 0.74569987158227022 kW (kilowatts).
- How many metric horsepower are in one horsepower?
- One horsepower = 1.013869665424 PS (metric horsepower).