Power converters

Convert between kilowatts and horsepower with our free, instant calculators.

About power conversion

Power measures the rate at which energy is transferred or work is performed. The two most commonly converted power units are kilowatts (kW) and horsepower (HP). Kilowatts are the metric standard used worldwide in engineering, electrical systems, and increasingly in vehicle ratings. Horsepower remains dominant in the United States and United Kingdom for describing engine output in cars, trucks, and motorcycles.

Converting between kW and HP is particularly important in the automotive industry, where manufacturers publish engine power figures in different units for different markets. A European car rated at 150 kW is the same as a US-market car rated at approximately 201 HP. The growing electric vehicle sector — which always rates motors in kW — has made this conversion more essential than ever.

Our power converters use the mechanical horsepower (1 HP = 745.69987 W), which is the most common definition for automotive and mechanical applications. This differs slightly from metric horsepower (PS, used in German/European specs) and electrical horsepower.

When do you need power conversion?

🚗 Automotive
Comparing car specs across US (HP) and European/Japanese (kW) markets. Electric vehicle motors are always rated in kW.
⚙️ Industrial machinery
Motors, generators, pumps, and compressors are rated in either kW or HP depending on the manufacturer and market.