How do you convert kW to horsepower?

To convert kilowatts to mechanical horsepower, multiply power in kW by 1.34102. HP (mechanical) = kW × 1.34102. The calculator on this page applies this formula automatically.

What is the difference between metric and mechanical horsepower?

Mechanical horsepower is defined as 745.699872 watts, while metric horsepower (PS) is defined as 735.49875 watts. For automotive and engineering usage in English-language contexts, mechanical horsepower is the most common choice.

Is this kW to HP converter suitable for motor and engine sizing?

Yes. The converter uses standard engineering definitions of kilowatt and mechanical horsepower and is appropriate for quick sizing checks of motors, pumps, fans and internal combustion engines.

kW to HP Converter – Convert Kilowatts to Horsepower

How to convert kW to HP

Power in kilowatts can be expressed in horsepower by applying a constant conversion factor that depends on the horsepower definition. This tool supports both mechanical horsepower and metric horsepower (PS).

Mechanical horsepower

1 HP_mech = 745.699872 W

1 kW = 1000 W

HP_mech = kW × 1000 / 745.699872 ≈ kW × 1.34102

kW = HP_mech × 745.699872 / 1000 ≈ HP × 0.74570

Metric horsepower (PS)

1 PS = 735.49875 W

HP_metric = kW × 1000 / 735.49875 ≈ kW × 1.35962

kW = HP_metric × 735.49875 / 1000 ≈ HP × 0.73550

Example: 5 kW to HP

Using mechanical horsepower:

HP = 5 × 1000 / 745.699872 ≈ 6.71 HP

Engineering use cases

Motor and pump sizing for HVAC and industrial equipment.
Estimating engine horsepower from rated electrical power.
Comparing European (kW) and US (HP) specifications on datasheets.

FAQ

Is 1 kW equal to 1.34 HP?

Yes, for mechanical horsepower the commonly used rounded factor is 1 kW ≈ 1.341 HP. The calculator uses the more precise constant 745.699872 W per HP internally.

Which horsepower should I use for cars?

In most English-language documentation and in North America, mechanical horsepower is used. In some European countries, metric horsepower (PS) still appears in legacy documentation.

Can I convert HP to kW with this tool?

Yes. Change the direction to “HP → kW” or press the swap button and enter the horsepower value. The result is shown immediately with the selected horsepower definition.