Horsepower & Torque Calculator
Solve for horsepower, torque, or RPM using HP = Torque × RPM / 5252. Results in HP, ft·lb, and Nm.
Engine Power Reference
| Engine / Vehicle | HP | Torque (ft·lb) | Peak RPM |
|---|---|---|---|
| Honda Civic 1.5T | 192 | 192 | 5,000 |
| Toyota Camry 2.5 | 203 | 184 | 5,700 |
| Ford F-150 5.0 V8 | 400 | 410 | 5,000 |
| Dodge Challenger 6.4 HEMI | 485 | 475 | 6,100 |
| Chevy Corvette Z06 5.5 V8 | 670 | 460 | 8,400 |
Frequently Asked Questions
What is the formula for horsepower and torque?
The fundamental relationship is: HP = Torque (ft·lb) × RPM / 5252. The number 5252 comes from unit conversions (33,000 ft·lbs/min per horsepower, divided by 2π). Rearranging: Torque = HP × 5252 / RPM, and RPM = HP × 5252 / Torque. Power and torque curves always intersect at exactly 5,252 RPM.
What is the difference between horsepower and torque?
Torque is the rotational force an engine produces — it determines how quickly you can accelerate from a stop or pull a heavy load. Horsepower is the rate at which work is done — it determines top speed. High torque at low RPM (like diesel engines) is ideal for towing. High horsepower at high RPM is ideal for top-end performance. Both matter depending on application.
What is 1 horsepower in watts?
1 mechanical horsepower = 745.7 watts (approximately 0.746 kW). So a 300 HP engine produces 300 × 745.7 = 223,710 watts ≈ 224 kW of power. Electric vehicle power is often rated in kilowatts — to convert kW to HP, multiply by 1.341.
How do I convert ft·lb to Nm?
1 ft·lb = 1.35582 Nm. To convert Nm to ft·lb, divide by 1.35582. Examples: 300 ft·lb = 407 Nm; 400 Nm = 295 ft·lb. European car specs typically use Nm while US specs use ft·lb. This calculator shows both automatically.
Why do diesel engines have more torque than gasoline engines?
Diesel engines produce more torque because of their higher compression ratio (18:1 to 23:1 vs. 8:1 to 12:1 for gasoline), larger displacement per cylinder, and the nature of the diesel combustion cycle — which builds pressure more slowly but over a longer crankshaft rotation. However, diesel engines rev less freely, so peak power (HP) may be lower despite higher peak torque.