Amps to Kilowatts Calculator
Enter current and voltage below — the kilowatts update instantly.
How do you convert amps to kilowatts?
Multiply amps by volts, then divide by 1,000. A 30 A load on a 240 V DC circuit draws 30 × 240 ÷ 1,000 = 7.2 kW. For AC single-phase, multiply by the power factor: kW = (A × V × PF) ÷ 1,000, so 30 A at 240 V with a power factor of 0.9 gives 30 × 240 × 0.9 ÷ 1,000 = 6.48 kW.
Amps to kW Formula
In a DC circuit there is no reactive power, so no power factor is needed. Divide by 1,000 to turn watts into kilowatts. Example: 50 A at 240 V is 50 × 240 ÷ 1,000 = 12 kW.
The power factor (PF) scales apparent power down to real power. Resistive loads (heaters) sit near 1.0; motors and electronics typically run 0.7 – 0.95.
The √3 factor (≈ 1.732) accounts for the phase angle between the three conductors. Voltage here is line-to-line (e.g. 400 V in Europe, 208 V or 480 V in the US).
Common Amps to kW Values (DC / PF 1.0)
| Current | at 120 V | at 230 V | at 400 V |
|---|---|---|---|
| 5 A | 0.60 kW | 1.15 kW | 2.00 kW |
| 10 A | 1.20 kW | 2.30 kW | 4.00 kW |
| 20 A | 2.40 kW | 4.60 kW | 8.00 kW |
| 30 A | 3.60 kW | 6.90 kW | 12.00 kW |
| 50 A | 6.00 kW | 11.50 kW | 20.00 kW |
| 100 A | 12.00 kW | 23.00 kW | 40.00 kW |
Frequently Asked Questions
How do I convert amps to kW?
Multiply the current in amps by the voltage in volts, then divide by 1,000. For DC: kW = (A × V) ÷ 1,000. For AC single-phase: kW = (A × V × PF) ÷ 1,000. For AC three-phase: kW = (√3 × A × V × PF) ÷ 1,000. Use the calculator at the top of this page for an instant result.
How many kW is 100 amps?
It depends on the voltage:
- 120 V DC: 100 × 120 ÷ 1,000 = 12 kW
- 240 V DC: 100 × 240 ÷ 1,000 = 24 kW
- 400 V three-phase (PF 0.9): √3 × 100 × 400 × 0.9 ÷ 1,000 = 62.35 kW
Does three-phase change the amps-to-kW formula?
Yes. Three-phase adds a √3 (≈ 1.732) factor because the load is shared across three conductors offset in phase: kW = (√3 × A × V × PF) ÷ 1,000. Use the line-to-line voltage (e.g. 400 V or 480 V).
What is the difference between amps and kilowatts?
Amps measure electric current; kilowatts measure real power. They are linked by voltage and power factor: kW = (A × V × PF) ÷ 1,000. The same current delivers far more power at a higher voltage — which is why transmission lines run at high voltage.