kw to amps calculator

Enter power, voltage, and system type to convert kilowatts (kW) into current (amps).

Power (kW)

Voltage (V)

System Type

Power Factor (0 to 1)

For resistive loads (like heaters), power factor is usually close to 1.0.

How to convert kW to amps

Converting kilowatts to amps helps you size cables, choose breakers, and estimate electrical load. The exact current depends on voltage, phase type, and power factor.

Core formulas

Single-phase AC: I = (kW × 1000) / (V × PF)

Three-phase AC: I = (kW × 1000) / (√3 × V × PF)

DC: I = (kW × 1000) / V

Where:

I = current in amps (A)
kW = power in kilowatts
V = voltage
PF = power factor (AC only)

Why power factor matters

In AC systems, power factor indicates how effectively electricity is converted into useful work. A lower power factor means more current is needed for the same real power. That can increase heat losses and require larger conductors.

Typical power factor ranges:

Heaters / incandescent loads: 0.95–1.00
Motors without correction: 0.75–0.90
Modern corrected equipment: 0.90–0.98

Worked examples

Example 1: Single-phase

A 5 kW load on 240 V single-phase at PF = 1.0:

I = (5 × 1000) / (240 × 1.0) = 20.83 A

Example 2: Three-phase

A 15 kW motor on 400 V three-phase at PF = 0.9:

I = (15 × 1000) / (1.732 × 400 × 0.9) ≈ 24.06 A

Example 3: DC system

A 2.4 kW DC load on 48 V:

I = (2.4 × 1000) / 48 = 50 A

Quick reference values

Power	System	Voltage	Power Factor	Current
1 kW	Single-phase AC	120 V	1.0	8.33 A
5 kW	Single-phase AC	240 V	1.0	20.83 A
10 kW	Single-phase AC	230 V	0.9	48.31 A
15 kW	Three-phase AC	400 V	0.9	24.06 A
30 kW	Three-phase AC	480 V	0.85	42.45 A

Practical sizing tips

Use nameplate values whenever available.
For continuous loads, many standards use 125% of running current when selecting overcurrent protection.
Check local code for conductor size, derating, and breaker rules.
Motor starting current can be much higher than running current.

FAQ

Is kW the same as kVA?

No. kW is real power. kVA is apparent power. In AC circuits: kW = kVA × PF.

Can I use this for generators or inverters?

Yes, for quick estimates. For final design, confirm surge capability, duty cycle, and manufacturer specifications.

Do I need an electrician?

If you're installing or modifying electrical systems, yes. This calculator is for estimation and planning, not a substitute for professional engineering or code compliance.