kW to Amps Calculator (AC/DC • 1-Phase / 3-Phase)

How to Use the kW to Amps Calculator

1) Choose AC or DC. 2) If AC, select 1-phase or 3-phase. 3) Enter your load in kW and your supply voltage (V). 4) For AC, enter power factor (PF). The calculator instantly outputs the current in amps (A).

3-Phase Voltage: L-L vs L-N

If your voltage is given as line-to-line (e.g., 400 V, 415 V, 480 V), use the L-L option. If your voltage is line-to-neutral (e.g., 230 V), use the L-N option.

Formulas Used

DC: I = (kW × 1000) / V

AC 1-Phase: I = (kW × 1000) / (V × PF)

AC 3-Phase (L-L): I = (kW × 1000) / (√3 × V × PF)

AC 3-Phase (L-N): I = (kW × 1000) / (3 × V × PF)

Apparent Power: kVA = kW / PF (AC only)

Example Calculation

A 10 kW, 3-phase load at 400 V (L-L) with PF 0.90: I ≈ (10 × 1000) / (√3 × 400 × 0.90) ≈ 16.04 A.

FAQ

Is kW the same as kVA?

No. kW is real power and kVA is apparent power. They are related by power factor (PF).

Why does PF increase amps?

Lower PF means more current is needed to deliver the same real power (kW).

Which voltage should I use for 3-phase?

Use L-L if your supply is specified as line-to-line (e.g., 400 V). Use L-N if specified line-to-neutral (e.g., 230 V).

What PF should I use if unknown?

For motors, 0.85–0.95 is common. For heaters/resistive loads, use 1.00.

Does DC need PF?

No. DC has no phase angle, so PF is 1.00 by definition.

Can I use this for breaker sizing?

Use it for estimation. Final sizing also depends on continuous load factors, starting current, cable method, and local code.

About This Tool

This MEPBase kW to amps calculator helps engineers quickly estimate current draw from real power (kW). Always verify final selections with project standards, utility conditions, and applicable codes.