Horsepower to kW Converter
Convert power ratings between mechanical HP, kilowatts, metric PS, and BTU/hr instantly.
Results
What is it?
Horsepower is a unit of power originally defined by James Watt. Today, three common variants exist: mechanical HP (used in the US, ≈745.7 W), metric PS or "Pferdestärke" (Germany and much of Europe, ≈735.5 W), and electrical HP (exactly 746 W). kW is the SI standard used worldwide in regulations and EV ratings.
How to use
Enter the power figure and choose its source unit from the dropdown. All four equivalent values are displayed simultaneously. Note that kW is the baseline — all conversions go through it.
Example scenario
A European sports car advertised as 400 PS is 294 kW, which equals 394 mechanical HP — about 1.5% less than PS, a common marketing nuance that confuses buyers comparing European and American specs.
Pro tip
Torque (lb-ft) and RPM relate to HP via the formula HP = Torque × RPM ÷ 5,252. So a 400 lb-ft engine at 4,000 RPM produces ≈304 HP regardless of displacement. Understanding this lets you interpret dyno sheets rather than relying on peak figures alone.