Kilowatts to horsepower converter

How to convert kW to hp

Multiply kilowatts by 1.341: hp = kW × 1.341. So 1 kW = 1.341 hp, 100 kW = 134.1 hp and 150 kW = 201.2 hp. That is mechanical horsepower; for metric horsepower (PS), common on European spec sheets, multiply by 1.3596 instead, so 100 kW = 136.0 PS.

Where 1.341 comes from

Kilowatts (kW) are 1,000 W, and a mechanical horsepower is 745.69987 W (NIST), so 1 kW = 1,000 ÷ 745.69987 = 1.3410221 hp.

The decimal never ends, so results are rounded; using 1.341 changes them by less than 0.002%.

Kilowatts to horsepower chart

Car and EV specs

European registration documents and brochures give engine power in kW, often with PS alongside. 110 kW is 147.5 hp but 149.6 PS, so a US and a European figure for the same engine differ by about 1.4%.

Electric motors are often quoted with a peak rating and a lower continuous rating. Convert the one that matches the figure you are comparing against.

Industrial motors and generators

Outside North America, motors are sized in kW. A 7.5 kW motor is 10.06 hp and a 0.75 kW motor is 1.006 hp, so those sizes line up with 10 hp and 1 hp motors.

A generator rated in kVA states apparent power. Multiply by the power factor on its nameplate to get kW before converting to horsepower.

kW versus kWh

A kilowatt-hour is energy: power multiplied by time. A machine running at 2 kW for three hours uses 6 kWh. An EV battery's kWh figure is stored energy, so it has no horsepower equivalent; the motor's kW rating does.

The energy converter handles kWh, joules and BTU.

Common mistakes

• Converting the power drawn instead of the shaft output. A motor drawing 10 kW at 90% efficiency delivers 9 kW at the shaft, which is 12.07 hp, not 13.41 hp.
• Quoting PS as hp. 100 kW is 136.0 PS but only 134.1 hp, so using the PS number in a US comparison overstates power by 1.4%.

Horsepower back to kilowatts

Multiply horsepower by 0.7457, or use the hp to kW converter. The power converter covers watts, BTU per hour and metric horsepower.