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.

Real power (W)

Required number input.

Reactive power (var)

Required number input.

Calculate the magnitude of complex power from real and reactive power. 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]

Complex power magnitude (VA)

The resulting complex power magnitude returned as a number.

• AC power calculations require a stated RMS convention and phase relationship. Nonsinusoidal waveforms, harmonics, unbalance, displacement versus true power factor, motor efficiency, and measurement bandwidth require waveform-aware analysis.
• 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.

• Ac Motor Reactive Power

  Calculate positive reactive-power magnitude for a balanced three-phase motor from line voltage, line current, and power factor.

• Motor Power Factor At Load

  Calculate balanced three-phase motor power factor as real input power divided by √3 times line voltage and line current; the result is a magnitude.

• Power Factor Calculator

  Calculate the power factor from resistance and impedance magnitude.