kW to Amps Calculator

Enter electrical input power in kW and the RMS voltage at the load terminals.

Convert active power into current using voltage, phase arrangement and power factor. Enter electrical input power in kW and the RMS voltage at the load terminals.

Active power and current calculator

Select conversion, AC phase, voltage and power factor to calculate current or electrical input power.

ConversionAC phaseVoltage at load terminals (V)Power factor (0-1)Electrical input power (kW)

Formula: I = 1000 × kW / (V × PF)

Planning estimate only. Use RMS voltage at the load terminals. Three-phase mode assumes a balanced load and line-to-line voltage. Confirm whether motor power is electrical input or shaft output before calculating current.

Choose single-phase or balanced three-phase AC

For single-phase AC, I = 1000 × P / (V × PF). For balanced three-phase AC, I = 1000 × P / (√3 × VLL × PF). The reverse calculation uses the same inputs to recover kW. Use line-to-line voltage in the three-phase mode.

System	kW to current	Current to kW
Single phase	I = 1000 × P / (V × PF)	P = V × I × PF / 1000
Balanced three phase	I = 1000 × P / (√3 × VLL × PF)	P = √3 × VLL × I × PF / 1000

Active power to line current. Electrical input power; illustrative balanced load.

Check the worked example

A 75 kW balanced load at 480 V and 0.90 power factor draws approximately 100.2 A. The calculation uses electrical input power. If the stated value is a motor's shaft output, obtain its input power or include the applicable efficiency before calculating input current.

Example	Inputs	Result
Balanced three-phase	75 kW · 480 V · PF 0.90	100.2 A
Single phase	10 kW · 240 V · PF 1.00	41.7 A
Reverse conversion	480 V · 100 A · PF 0.90 · balanced three-phase	74.8 kW

Use the result in the equipment schedule

Label the result with voltage, phase and power factor. Keep starting current and nonlinear-load behavior as separate design inputs. Use the kVA conversion tool when the load specification is already given in apparent power.

Convert kVA to Amps

Use the transformer rating or apparent-power value to calculate current.

Size the Transformer

Bring operating demand, voltage, phase and expansion into the equipment schedule.

Review Pad-Mounted Transformers

Compare distribution transformer configurations for site requirements.

Review Dry-Type Transformers

Connect current and voltage requirements to indoor equipment options.

Frequently asked questions

Which power value belongs in the input?

Enter electrical input kW for the operating condition being evaluated. For a motor's shaft output, obtain electrical input power or account for applicable efficiency.

Is power factor the same as efficiency?

Power factor relates kW to kVA. Efficiency relates useful output power to input power.

Apply the calculation to your equipment

Use the calculated current with the equipment schedule, transformer voltage and project specification.