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Calixo

Power Factor Calculator

Find the power factor of an electrical load from real and apparent power.

Inputs

Saved Scenarios

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Power Factor

0.800

Spark says

How it's calculated

Formula

PF=Real PowerWApparent PowerVAPF = \dfrac{Real\ Power_{W}}{Apparent\ Power_{VA}}
Real\ Power
— Power that actually does useful work
Apparent\ Power
— Voltage × current, ignoring phase

What is the Power Factor Calculator?

Power factor measures how effectively electrical power is converted into useful work — a value of 1.0 means all supplied power does work, while a lower value means some current flows without contributing useful power (common with inductive loads like motors).

How to use it

  1. 1 Enter the real (working) power in watts.
  2. 2 Enter the apparent power in volt-amps.

Worked examples

800W real, 1000VA apparent

Power factor is 0.8.

Try it

Frequently asked questions

Why do utilities penalize low power factor?

A low power factor means more current has to flow to deliver the same real power, increasing losses and requiring larger infrastructure — many commercial utility tariffs charge a penalty below a threshold (often 0.9).