What is the magic number 5252?

5252 = 33,000 / (2π). It converts the units of torque (lb·ft) and RPM into horsepower. At 5252 RPM, torque and horsepower curves always intersect.

What is metric horsepower (PS)?

PS (Pferdestärke) is the European metric unit. 1 PS = 75 kgf·m/s ≈ 0.9863 HP. It is commonly used for car specifications in Europe and Asia.

Is horsepower the same as kilowatts?

No — 1 HP = 0.7457 kW. Many countries use kW for engine ratings. The calculator shows both.

What is the Force & Velocity method used for?

It is useful for linear systems like electric motors driving conveyor belts or hoists, where you know the pulling force and speed rather than rotational torque.

How is electrical horsepower different?

Electrical horsepower (used for motors) = 746 W exactly, while mechanical horsepower = 745.7 W. The difference is small and the calculator uses 745.7 W.

Everyday

↵ to calculate

Horsepower Calculator - kW to HP Converter Calculator Online

Calculate horsepower from torque and RPM, force and velocity, or watts using three different methods.

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How to use this calculator

👉 Fill in the boxes below and your answer appears instantly — no maths needed, we do it all for you! 🎉

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In plain English — what does this do?

📏 Some countries say ‘30 degrees’ and others say ‘86 degrees’ for the same weather! Some say ‘5 km’, others say ‘3 miles’. This tool swaps between them instantly so you always know what it means.

📌 Direct Answer & Summary

The Horsepower Calculator converts mechanical power measurements into horsepower (HP), kilowatts (kW), and metric horsepower (PS). It supports three input methods: torque and RPM, force and velocity, or direct wattage conversion.

Method

Torque (lb·ft)

RPM

What is Horsepower Calculator - kW to HP Converter Calculator Online?

How to use it

1️⃣ Select the calculation method: Torque & RPM, Force & Velocity, or Watts.
2️⃣ Enter the values for your chosen method.
3️⃣ Click Calculate to get horsepower, kilowatts, and metric horsepower.
4️⃣ Use the Torque & RPM method for engines — this is the most common method.
5️⃣ Use the Watts method to convert between electrical and mechanical power ratings.

Formula

From torque: HP = Torque (lb·ft) × RPM / 5252. From force/velocity: HP = Force (lbf) × Velocity (ft/s) / 550. From watts: HP = Watts / 745.7. Kilowatts = HP × 0.7457. Metric HP (PS) = HP × 1.01387.

💡 See it in action — a real example

An engine producing 300 lb·ft of torque at 5000 RPM: HP = 300 × 5000 / 5252 = 285.6 HP = 213 kW = 289.5 PS.

❓ Common questions

What is the magic number 5252?: 5252 = 33,000 / (2π). It converts the units of torque (lb·ft) and RPM into horsepower. At 5252 RPM, torque and horsepower curves always intersect.
What is metric horsepower (PS)?: PS (Pferdestärke) is the European metric unit. 1 PS = 75 kgf·m/s ≈ 0.9863 HP. It is commonly used for car specifications in Europe and Asia.
Is horsepower the same as kilowatts?: No — 1 HP = 0.7457 kW. Many countries use kW for engine ratings. The calculator shows both.
What is the Force & Velocity method used for?: It is useful for linear systems like electric motors driving conveyor belts or hoists, where you know the pulling force and speed rather than rotational torque.
How is electrical horsepower different?: Electrical horsepower (used for motors) = 746 W exactly, while mechanical horsepower = 745.7 W. The difference is small and the calculator uses 745.7 W.

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