Power Factor Calculator
Power factor, reactive power (kVAR) and phase angle from measured real power, voltage and current.
Inputs
kW
V
A
Results
- Power factor
- 0.833
- Apparent power
- 18.01 kVA
- Reactive power
- 9.97 kVAR
- Phase angle
- 33.6 °
Formula
S (kVA) = V × I (× √3 for three-phase) ÷ 1000
PF = P ÷ S
Q = √(S² − P²)
Assumptions & limits
- Balanced sinusoidal load; harmonics lower the true power factor.
- Use simultaneous readings from a power analyser.
Worked example
S = 400 × 26 × 1.732 ÷ 1000 = 18.01 kVA; PF = 15 ÷ 18.01 = 0.833.