Power Factor Calculator

Calculate power factor from kW and kVA, watts and volt-amps, volts and amps, or phase angle. This calculator also estimates apparent power, reactive power, phase angle, kVAR, and power factor correction.

Calculate Power Factor

Power factor = real power ÷ apparent power. PF = kW ÷ kVA.
Your result will appear here.

How the power factor calculator works

Power factor:
The calculator divides real power by apparent power to estimate power factor.

Reactive power:
It estimates kVAR using the power triangle relationship between kW, kVA, and kVAR.

Correction estimate:
The calculator estimates how much kVAR correction may be needed to reach a target power factor.

Why use a power factor calculator?

A power factor calculator helps estimate how efficiently AC electrical power is being used by motors, transformers, HVAC equipment, lighting, and industrial loads.

It can help with kW, kVA, kVAR, phase angle, power factor correction planning, capacitor bank estimates, and electrical load analysis.

What your result means

Your result shows power factor, kW, kVA, kVAR, phase angle, apparent current, correction kVAR, corrected kVA, estimated capacitor size, and comparison load power factors.

Power factor calculator formulas

Frequently asked questions

How do I calculate power factor?

Divide real power by apparent power. For example, 8 kW divided by 10 kVA gives a power factor of 0.80.

What is a good power factor?

A power factor close to 1.00 is generally better. Many facilities target around 0.95 or higher, but the best target depends on the utility and equipment.

What causes low power factor?

Inductive loads such as motors, transformers, compressors, ballasts, and some industrial equipment can lower power factor.

Can this replace a professional power factor correction design?

No. This calculator gives a simplified estimate. Power factor correction requires review of harmonics, switching, utility rules, equipment ratings, capacitor placement, and electrical code.