Torque to Horsepower Calculator

HP = T × RPM / 5252. Converts engine torque to power at given RPM.

Inputs

Result

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General calculation reads

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How to use this calculator

  • Enter torque + RPM.
  • Read HP + kW.

About this calculator

Power = torque × angular velocity. In US units: HP = T (lb-ft) × RPM / 5252. A diesel making 600 lb-ft at 1800 RPM = 206 HP. A redlined NA gas engine at 7000 RPM × 200 lb-ft = 266 HP. Torque is what you feel; HP is the long-distance/work-rate measure. Two engines making the same HP feel very different depending on the RPM where they make peak torque.

Frequently asked

Diesel vs. gas?+
Diesels make huge torque at low RPM (long stroke, high compression). Gas engines rev to high RPM. Both can make 300+ HP.
EVs really skip the math?+
Same physics, but instant torque from 0 RPM. EV motors red-line ~12,000-18,000 RPM. Power curve is roughly flat across mid-range.
When does HP matter most?+
Top speed, sustained heavy load, hill climbs. HP × 0.0006 = top speed (mph) in a aerodynamically average car.
Crank HP vs. wheel HP?+
Wheel HP is 10-15% lower than crank (drivetrain losses). Manufacturers spec crank; dynos measure wheel.
Torque per liter?+
NA gas: 70-100 lb-ft/L. Turbo gas: 100-180 lb-ft/L. Diesel: 100-150 lb-ft/L. EV: not applicable (no displacement).

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