A familiar situation
Vergleichen Sie Leistungsangaben, wenn Messwerte in unterschiedlichen Drehmomenteinheiten vorliegen.
How to use this calculator
- Enter torque, engine speed, torque unit.
- Select Calculate to see the answer and its breakdown.
- Keep a scenario, change an input and compare the results.
Use consistent units and check the assumptions below before applying the result.
How engine horsepower is calculated
Estimate engine power from torque and engine speed, with explicit choices for lb-ft or newton-meters and horsepower or kilowatts. Torque and RPM must refer to the same operating point; peak torque and peak RPM from different points cannot be combined into peak power. A torque reading of 300 lb-ft at 4,000 rpm is about 228 hp. The calculation validates each input and keeps its stated units explicit. Power is torque multiplied by rotational speed, so falling torque can be offset by rising RPM. This is an estimate for the stated assumptions; confirm measurements and any applicable professional or local standards before relying on it.
hp = torque(lb-ft) × rpm ÷ 5252A torque reading of 300 lb-ft at 4,000 rpm is about 228 hp.
Assumptions & useful context
The result depends on the values you enter and the method described above. Displayed numbers may be rounded; calculations use the unrounded values. Check that this model matches your situation before relying on it.
Frequently asked questions
Why can peak horsepower occur above peak torque RPM?
Power is torque multiplied by rotational speed, so falling torque can be offset by rising RPM.
Does this include drivetrain loss?
No. It estimates power at the shaft represented by the torque measurement.