PowerConvert™ Fast Electrical Power Calculators
Amps to kW Calculator
Turn a measured current into real power in kilowatts. Enter the amps with the system voltage, phase, and power factor.
How it is calculated
For three phase, kW = (1.732 x volts x amps x power factor) / 1000. For single phase, drop the 1.732.
At 400 V, 1 A, power factor 0.8, three phase: kW = (1.732 x 400 x 1 x 0.8) / 1000 = 0.55 kW.
Frequently asked questions
How do you convert amps to kW?
Multiply the voltage, amps, and power factor, then divide by 1000. For three phase also multiply by 1.732: kW = (1.732 x volts x amps x power factor) / 1000.
Why multiply by 1.732 for three phase?
1.732 is the square root of 3. It relates the line voltage and current to the total power across the three conductors of a three phase supply.
What is the difference between kW and kVA?
kW is real (working) power; kVA is apparent power, the total the supply has to deliver. They are linked by the power factor: kW = kVA x power factor.