What is the HP to kW Calculator?
This calculator converts power expressed in horsepower (HP) into kilowatts (kW), the SI unit of power. It uses mechanical (imperial) horsepower, where 1 HP equals 0.7457 kW (745.7 watts). This is handy for comparing engine, motor, or pump ratings between specifications that use different units.
How to Use It
Enter the power value in horsepower and the calculator instantly returns the equivalent in kilowatts. The result updates using a simple multiplication, so you can quickly check vehicle, generator, or appliance ratings.
The Formula Explained
The conversion is a direct proportion: $$P_{\text{kW}} = \text{Power (HP)} \times 0.7457$$. One mechanical horsepower is defined as 550 foot-pounds per second, which equals approximately 745.7 watts, or 0.7457 kilowatts. To reverse the conversion, divide kilowatts by 0.7457 (or multiply by about 1.341) to get horsepower.
Worked Example
Suppose a car engine is rated at 150 HP. Multiply: $$150 \times 0.7457 = 111.855 \text{ kW}$$ So a 150 HP engine produces roughly 111.86 kilowatts of power.
FAQ
Which horsepower does this use? It uses mechanical (imperial) horsepower (\(1 \text{ HP} = 0.7457 \text{ kW}\)). Metric horsepower (PS) is slightly different at 0.7355 kW.
How do I convert kW back to HP? Divide the kilowatts by 0.7457, or multiply by approximately 1.341.
Is kW the same as kWh? No. Kilowatts (kW) measure power (rate of energy use), while kilowatt-hours (kWh) measure energy consumed over time.
