OhMyCalc

Engine Horsepower Calculator

Calculate engine horsepower from torque and RPM. Get results in HP and kilowatts using the metric formula.

How to Use the Engine Horsepower Calculator

  1. Enter the known physical values in the corresponding fields.
  2. Select the appropriate units if multiple options are available.
  3. The unknown value is computed instantly from the formula.
  4. Review the result and the formula explanation below.

مرجع سريع

منإلى
Speed of light299,792,458 m/s
Gravity (g)9.807 m/s²
Avogadro's number6.022 × 10²³
Boltzmann const.1.38 × 10⁻²³ J/K
Elementary charge1.602 × 10⁻¹⁹ C
Planck's const.6.626 × 10⁻³⁴ J·s

حالات الاستخدام

الصيغة

HP = Torque (Nm) × RPM / 7121. kW = HP × 0.7457.

الأسئلة الشائعة

How to use?
Enter the data and click the calculate button.
Why divide by 7121?
The constant 7121 converts from Newton-meters and RPM to metric horsepower. For imperial (ft·lbf), use 5252 instead.
What is the difference between HP and kW?
Horsepower (HP) and kilowatts (kW) both measure power. 1 HP equals approximately 0.7457 kW.
Is it free?
Yes, all calculators are completely free.