Torque to kW Calculator

Convert rotational torque to power output in kilowatts and horsepower.

Power Calculator:

Convert torque measurements to actual power output for engines, motors, and rotating machinery across automotive and industrial applications.

Torque to Power Converter

Rotational torque measurement

Rotational speed measurement

Power Calculation Results

Enter torque and speed, then click "Calculate"

to see power output results

Torque to Power Conversion

Torque alone doesn't tell the complete story about how powerful an engine or motor really is. True power depends on both the torque produced and how fast the shaft rotates. A high-torque engine at low RPM might produce less power than a moderate-torque engine spinning much faster.

This calculator bridges the gap between torque measurements and actual power output, helping engineers, mechanics, and enthusiasts understand real-world performance. Whether you're working with car engines, industrial motors, or any rotating machinery, knowing the power output is crucial for proper sizing and performance analysis.

Power Calculation Formulas

Power is calculated using torque and rotational speed:

Using RPM (Revolutions per Minute)
Power (kW) = (Torque (Nm) × RPM × 2π) ÷ 60,000
*2π converts RPM to radians per second
Using Angular Speed (rad/s)
Power (kW) = Torque (Nm) × Angular Speed (rad/s) ÷ 1000
*Direct calculation when speed is in radians per second

For horsepower comparison:

  • 1 kW = 1.341 HP (mechanical horsepower)
  • 1 kW = 1.3596 HP (metric horsepower)

Engine Power Examples

Here are practical power calculations for different engines and motors:

Torque (Nm) Speed (RPM) Power (kW) Power (HP)
100 1500 15.7 21.1
200 3000 62.8 84.3
350 4000 146.6 196.7
50 6000 31.4 42.1
150 2000 31.4 42.1
250 5000 130.9 175.7
75 8000 62.8 84.3
300 3500 109.9 147.5
180 4500 85.0 114.0
120 2500 31.4 42.1
400 3000 125.7 168.6
85 7000 62.4 83.7
220 3800 87.6 117.5
160 3200 53.7 72.1
280 4200 123.2 165.2
95 5500 54.8 73.5
320 2800 93.7 125.7
140 4800 70.4 94.4
190 3600 71.6 96.1
260 3300 89.9 120.6
110 5200 59.9 80.4
340 3100 110.4 148.1
Engineering Tip:

Remember that peak torque and peak power occur at different RPMs. A motor might have maximum torque at 2000 RPM but maximum power at 4000 RPM. This calculator helps you understand power delivery across the entire operating range.