Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

Speed constant (rpm/V) (rpm/V)

Required number input.

Convert a brushless motor speed constant in RPM per volt to ideal torque constant in newton-meters per ampere using 60/(2πKv); winding and measurement conventions must match. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Torque Constant (N·m/A) (N·m/A)

The resulting torque constant (n·m/a) returned as a number.

• Motor constants, current, torque, speed, reactive power, and propeller thrust depend on winding temperature, controller, supply sag, losses, saturation, load curve, airflow, and operating point. Nameplate constants and ideal propeller laws need test data for final sizing.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

• Torque Constant Kt

  Compute the torque constant Kt in newton meters per ampere from the motor velocity constant Kv using Kt = 60 / (2 * pi * Kv).

• Motor Back EMF

  Compute the back EMF of a brushless motor in volts as shaft speed divided by its Kv constant in rpm per volt.

• Mechanical Power

  Compute mechanical output power in watts from torque in newton meters times angular speed in radians per second.