Power Converter
Convert power between watts, kilowatts, megawatts, horsepower (mechanical and metric) and BTU per hour. One mechanical horsepower is 745.7 watts.
Enter a value
Result
1 horsepower, mechanical (hp) =
0.7457 Kilowatt (kW)
1 × 0.7457 = 0.7457
Show the working
- 1. Convert 1 Horsepower, mechanical (hp) to watts: 1 × 745.7 = 745.7.
- 2. Convert to Kilowatt (kW): 745.7 ÷ 1,000 = 0.7457.
1 Horsepower, mechanical (hp) in every unit
Everyday power levels
- LED light bulb
- 10 W
- Electric kettle
- 2,000 W
- Small car engine
- 75 kW ≈ 100 hp
- Window air conditioner
- 5,000 BTU/h ≈ 1.5 kW
- Wind turbine
- 3 MW
- Large power station
- 1,000 MW
Good to know: Car engines use metric or mechanical hp (735.5 W vs 745.7 W) — about 1.4% apart.
About this tool
Convert power between watts, kilowatts, horsepower and BTU/h — for engines, motors and heating or cooling equipment.
Formula
1 hp (mechanical) = 745.69987 W; 1 hp (metric, PS) = 735.49875 W; 1 BTU/h = 0.29307107 W.
Reference values
- 1 hp = 745.7 W
- 1 BTU/h = 0.2931 W
- 1 kW = 1.341 hp
Questions people ask
How many watts is one horsepower?
Mechanical (US) horsepower is 745.69987 W exactly; metric horsepower (PS) is 735.49875 W.
How many watts is a BTU per hour?
1 BTU/h = 0.29307107 W. Air conditioners are often rated in both: 12,000 BTU/h ≈ 3.5 kW.
Why do electric cars use kW instead of hp?
kW is the SI unit, so it is unambiguous — 150 kW is the same power whether you are in Europe or the US (about 201 mechanical hp).
Related tools
How we calculate this
Power units follow the SI watt and the internationally agreed definitions of mechanical horsepower (745.69987 W), metric horsepower (735.49875 W) and the BTU (1,055.05585 J). Source: NIST Handbook 44 (Appendix C).
Spotted a mistake? Tell us and we'll check it. How we check our calculators