What Is the Horsepower to kW Converter?
This tool converts mechanical horsepower (hp) into kilowatts (kW), the SI unit of power. Both units measure the rate at which energy is used or work is done, but horsepower is common for engines and motors in the US and UK, while kilowatts are the international standard. The converter uses the widely accepted factor \(1\ \text{hp} = 0.7457\ \text{kW}\) (imperial/mechanical horsepower).
How to Use It
Enter the power value in horsepower and the calculator instantly returns the equivalent in kilowatts. To go the other way, simply divide your kilowatt figure by 0.7457 to recover horsepower.
The Formula Explained
Power conversion is a direct linear scaling: $$\text{kW} = \text{Horsepower (hp)} \times 0.7457$$ The constant 0.7457 comes from the definition of one mechanical horsepower as 550 foot-pounds per second, which equals approximately 745.7 watts, or 0.7457 kilowatts. Note that metric horsepower (PS/CV) is slightly different at 0.7355 kW; this calculator uses the mechanical horsepower standard.
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 about 111.86 kW.
FAQ
Is horsepower the same as metric horsepower? No. Mechanical (imperial) horsepower equals 0.7457 kW, while metric horsepower (PS) equals 0.7355 kW. This tool uses mechanical horsepower.
How do I convert kW back to hp? Divide the kilowatts by 0.7457. For example, \(75\ \text{kW} \div 0.7457 \approx 100.6\ \text{hp}\).
Why convert hp to kW? Kilowatts are the SI standard used worldwide, on EV motor ratings, and in many vehicle registration documents, so converting helps compare specs across regions.
