How to use the power factor calculator
Find real, reactive and apparent power in an AC circuit. Enter voltage, current, power factor in the fields above; the apparent power, real power, reactive power are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- V — Voltage (V)
- I — Current (A)
- pf — Power factor
Worked example
With voltage = 230 V, current = 10 A, power factor = 0.85, the calculator gives apparent power ≈ 2,300 VA; real power ≈ 1,955 W; reactive power ≈ 1,211.6 var.
Frequently asked questions
What is the formula for the power factor calculation?
Apparent power (VA) = V × I. Real power (W) = [Apparent power] × pf. Reactive power (var) = [Apparent power] × √(1-pf × pf). Here V is voltage (V), I is current (A), pf is power factor.
What inputs do I need for the power factor calculator?
You need voltage in V, current in A, power factor. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.