Electrical
Torque, Power & RPM
Calculate the relationship between torque, power and rotational speed
N·m
RPM
Result
Power15,184 kW
Watts15 184,4 W
Horsepower (hp)20,36 hp
Metric PS20,64 PS
How does it work?
Torque (T, N·m) is the rotational force — force multiplied by the distance from the axis. Higher torque means better pulling force.
Rotational speed (n, RPM) is the number of revolutions per minute.
Power (P, kW) is the rate of energy conversion. The relationship:
P (kW) = T (N·m) × n (RPM) × 2π / 60 000
2π converts revolutions to radians; 60 000 converts minutes to seconds and watts to kilowatts.
Example
Example (car engine): Diesel engine with peak torque 320 N·m @ 2000 RPM.
→ Power: 320 × 2000 × 2π / 60 000 = 67.0 kW (91 PS)
Example 2 (electric motor): 11 kW motor at 1450 RPM.
→ Torque: 11 × 60 000 / (1450 × 2π) = 72.4 N·m
Assumptions
- •Formula applies at steady-state RPM (acceleration not considered)
- •Torque T is assumed constant at the given RPM
- •Mechanical losses (bearings, gearbox) are not included