Convert kilowatts to amps for DC, single-phase AC and three-phase circuits. Enter the power in kW, the voltage and the power factor, and see the kVA too. Free, private, and runs entirely in your browser.
Convert the power to watts by multiplying by 1,000, then divide by the voltage. AC circuits include the power factor, and three-phase circuits add the square root of 3 for line-to-line voltage.
How many amps is 1 kW? At 120 V it is 8.33 A, and at 240 V it is 4.17 A, for a power factor of 1.
How many amps is 10 kW three-phase? At 400 V and a power factor of 0.9, about 16.04 A. At 208 V it is about 30.8 A.
A 10 kW three-phase load runs on 400 V with a power factor of 0.9. Current = 10,000 ÷ (1.732 × 400 × 0.9) ≈ 16.04 A, and the apparent power is 10 ÷ 0.9 ≈ 11.11 kVA. For 5 kW on single-phase 240 V with a power factor of 1, current = 5,000 ÷ 240 ≈ 20.83 A.
What is the difference between kW and kVA? kW is real power. kVA is voltage times current, and equals kW only when the power factor is 1.
Is a bigger breaker always safer? No. The breaker protects the wire, so it must match the wire rating, not just the load.
The kilowatt combines the watt, named for the Scottish engineer James Watt, with the prefix kilo, which means 1,000 and entered the metric system in the 1790s. Electric utilities adopted the kilowatt-hour as the unit for selling energy, and most appliance and motor ratings are still given in kW or horsepower.
Use this calculator to size circuits and cables for a heater, motor, EV charger or generator. A 7.2 kW EV charger on 240 V single-phase draws 30 A, which is why it needs a dedicated circuit. Always have an electrician confirm wire and breaker sizes.
How do I convert kW to amps without power factor? Use a power factor of 1 for resistive loads such as heaters. For motors, use the nameplate value or about 0.8 to 0.9.
How do I convert amps back to kW? Use the amps to watts calculator and divide the watts by 1,000.