Motor Power Calculator

Our Motor Power Calculator simplifies the physics behind rotary motion. Since mechanical power (P) is fundamentally defined as the product of torque ($\tau$) and angular velocity ($\omega$), this tool allows you to calculate the output power in Watts (W) or horsepower (hp). You simply input two key values: the operating Torque (measured in Newton-meters, Nm) and the rotational speed (in Revolutions Per Minute, RPM).

The calculator handles the complex unit conversions internally. It uses the relationship $P = \frac{\tau \cdot N}{9549}$ to deliver accurate results, converting your input units into standard power metrics. For example, if you enter a 10 Nm torque and a 3000 RPM speed, the tool instantly provides the resulting power output.

• Torque ($\tau$): The rotational force applied (Nm).
• RPM: Rotational speed in revolutions per minute.
• Power Output (P): The resulting mechanical power (W or hp).

To get the most reliable power calculation, consider defining your operational parameters precisely. Power is dynamic; it changes as load and speed change throughout a cycle.

• Calculate at Operating Point: Instead of using the maximum possible torque or RPM, use the values expected during normal operation (e.g., 80% load capacity).
• Consider Duty Cycle: For intermittent applications, note the duty cycle time. This helps determine if the motor will overheat even if the average power is low.

If your application involves variable speed operation (VFD), run the calculation at several key points (e.g., startup torque, cruising torque, and maximum load) to ensure adequate margin.