Horsepower Calculator
Calculate horsepower from torque and RPM, watts, kilowatts, or force and speed. See equivalent power units, formulas, and a clear step-by-step result.
Select torque and RPM, electrical power, or force and speed.
Use the units that match your engine, motor, or mechanical system.
Review mechanical HP, metric HP, watts, kilowatts, and conversions.
HP = Watts ÷ 745.6999
HP = Force × Speed ÷ 745.6999
Using 300 lb-ft of torque at 1,000 RPM: horsepower = 300 × 1,000 ÷ 5,252 = 57.12 hp. This equals approximately 42.59 kW and 57.91 metric horsepower.
What is horsepower?
Horsepower is a unit of power that describes how quickly work is performed. Mechanical horsepower equals approximately 745.7 watts.
Why is 5252 used in the torque formula?
The constant 5252 comes from converting rotational speed and torque units into mechanical horsepower. At 5252 RPM, torque in lb-ft and horsepower are numerically equal.
Is metric horsepower the same as mechanical horsepower?
No. One metric horsepower, often written PS, is about 735.5 watts, while one mechanical horsepower is about 745.7 watts.
Does this calculate wheel or engine horsepower?
It calculates power from the values entered. Whether that represents wheel or engine horsepower depends on where the torque or power was measured.
Results are estimates generated locally in your browser from standard scientific formulas and reference data. They are for informational and educational purposes only and are not a substitute for laboratory validation or professional scientific analysis. VisionVix accepts no liability for decisions based on this tool's output.
This calculator provides general engineering estimates. Real-world engine and motor output can vary because of drivetrain losses, measurement conditions, and equipment efficiency.
