Calculator
Power Factor Calculator
Change the inputs to match your equipment. Results update automatically.
Formula
cos phi = kW / kVAtan phi = sqrt(1 - cos^2 phi) / cos phi Worked example
15 kW / 20 kVA = 0.75. This ratio does not by itself identify whether the load is leading or lagging.
Scope and interpretation
Use matching measurements from the same operating condition. The ratio must be between zero and one.