Enter Values
Formula
kW = V × A × PF ÷ 1000
kVA = V × A ÷ 1000
PF is the power factor from greater than 0 through 1.
Example
At 240 V, 20 A, and 0.90 PF: real power is 4.32 kW and apparent power is 4.80 kVA.
Understanding the Inputs
- Voltage: RMS voltage across the single-phase load.
- Current: RMS current drawn by the load.
- Power factor: real power divided by apparent power, from greater than 0 through 1.
For a nearly resistive load, power factor may be close to 1. Motors, transformers, and electronic equipment can have lower power factor.
What the Results Mean
Kilowatts measure real power converted into useful work or heat. Kilovolt-amperes measure apparent power carried by the source and conductors. A low power factor increases current and kVA for the same real power.
This calculator does not include efficiency. If you start with mechanical output power, include equipment efficiency before comparing it with electrical input power.