Engine Horsepower Calculator
HP from Torque & RPM
Calculate horsepower from torque and engine RPM
lb-ft
HP from Displacement (estimate)
Estimate horsepower from engine displacement
L
Power Unit Converter
Convert between HP, kW, and PS
Formula
HP = (Torque x RPM) / 5252
Frequently Asked Questions
How is horsepower calculated from torque?
HP = (Torque x RPM) / 5252. At 5,252 RPM, horsepower and torque (in lb-ft) are always equal. Below that RPM, torque is higher; above it, HP is higher.
What is the difference between HP, kW, and PS?
HP (mechanical horsepower) is used in the US and UK. kW (kilowatts) is the SI unit used internationally. PS (Pferdestärke) is the metric horsepower used in Europe and Japan. 1 HP = 0.7457 kW = 1.01387 PS.