This power factor calculator finds the power factor from real and apparent power, or from voltage and current. Enter your values above to get PF and the phase angle.
Formulas
Power factor = P (kW) ÷ S (kVA) = cos φ Single phase: P = V × I × PF
Example
8 kW real, 10 kVA apparent: PF = 8 ÷ 10 = 0.8, phase angle = cos⁻¹(0.8) = 36.9°.
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Frequently Asked Questions
How do I calculate power factor?
Divide real power (kW) by apparent power (kVA). A 8 kW load drawing 10 kVA has a power factor of 0.8.
What is a good power factor?
0.95 or higher is considered good. A low power factor wastes capacity and may incur utility penalties.
How is power factor corrected?
By adding capacitors that supply reactive power, which raises the power factor toward 1 and lowers the current drawn.