Engineering calculators

kW to Amps Calculator

Updated Jun 4, 2026 By Jehan Wadia
Current Type
Inputs
Decimals & scientific notation OK (e.g. 5e3).
Must be greater than zero.
Decimal places (0–8).
Result
Current
— A
Power (kW)
Voltage (V)
Power Factor
Mode
I(A) = 1000 × P(kW) / V(V)
Current vs. Voltage (at current Power)

Introduction

This kW to Amps calculator converts kilowatts (kW) to amperes (A) for DC, AC single phase, and AC three phase circuits. Just enter your power, voltage, and power factor, and the tool gives you the current in amps right away. It works for milliwatts (mW), watts (W), and kilowatts (kW), so you can use it for small electronics or large industrial loads.

Knowing how many amps a device draws is important when you pick wire sizes, circuit breakers, or fuses. Instead of doing the math by hand, this calculator applies the correct formula for each current type. For DC, it divides power by voltage. For AC single phase, it accounts for the power factor. For AC three phase, it uses either the line-to-line or line-to-neutral formula with the √3 factor. The tool also shows a chart of how current changes as voltage goes up or down, so you can see the relationship clearly.

How to Use Our kW to Amps Calculator

Enter your power, voltage, and current type below. The calculator will instantly convert your kilowatts (kW) into amps (A).

Current Type: Pick the type of electrical current you are working with. Choose DC for batteries and solar panels, AC Single Phase for most home outlets, or AC Three Phase for industrial motors and large equipment.

Power: Type in the amount of power. Use the dropdown next to it to select milliwatts (mW), watts (W), or kilowatts (kW). If you need to work with power in a broader context, our Power Calculator can help with additional conversions and calculations.

Voltage: Type in the voltage of your circuit. Use the dropdown to select millivolts (mV), volts (V), or kilovolts (kV). This value must be greater than zero. If you need to check voltage relationships in your circuit, try our Voltage Divider Calculator.

Power Factor: This field only shows for AC circuits. Enter a number between 0.01 and 1. If you do not know your power factor, use 1 for a purely resistive load or 0.8 as a common estimate for motors.

Voltage Reference: This field only shows for three-phase AC. Choose Line to Line if you measured voltage between two hot wires. Choose Line to Neutral if you measured voltage between one hot wire and neutral.

Result Precision: Choose how many decimal places you want in your answer. You can pick any number from 0 to 8.

Press Calculate to see your result, or press Reset to clear all fields and start over. The chart below the result shows how the current changes as voltage goes up or down at your chosen power level.

How to Convert kW to Amps

Converting kilowatts (kW) to amps (A) means finding how much electric current flows through a circuit when you know the power and voltage. Power tells you how much energy a device uses. Voltage is the force that pushes electricity through a wire. Current, measured in amps, is the amount of electricity actually flowing. You need both power and voltage to find the current. For the foundational relationship between these quantities, our Ohm's Law Calculator is a helpful companion tool.

The Basic Formula

For a DC circuit, the formula is simple:

I (A) = 1,000 × P (kW) ÷ V (V)

You multiply the power in kilowatts by 1,000 to convert it to watts, then divide by the voltage in volts. The answer is the current in amps.

AC Circuits Are Different

AC circuits need one extra value called the power factor (PF). The power factor is a number between 0 and 1 that shows how efficiently the circuit uses electricity. A power factor of 1 means all the power is being used. Motors, compressors, and other devices with coils often have a power factor between 0.8 and 0.95.

For single-phase AC:

I (A) = 1,000 × P (kW) ÷ (PF × V)

For three-phase AC using line-to-line voltage:

I (A) = 1,000 × P (kW) ÷ (√3 × PF × V)

For three-phase AC using line-to-neutral voltage:

I (A) = 1,000 × P (kW) ÷ (3 × PF × V)

The √3 (square root of 3, which equals about 1.732) appears in three-phase calculations because three-phase power uses three wires that carry current in a balanced pattern. For a deeper dive into three-phase systems, our 3 Phase Power Calculator covers power, current, and voltage relationships in detail.

When You Need This Conversion

Electricians and engineers use kW to amps conversion to pick the right wire size, choose the correct circuit breaker, and make sure electrical panels can handle the load. If you know a machine uses 5 kW on a 240V single-phase circuit with a power factor of 0.9, this conversion tells you the wire must carry about 23.15 amps. That information helps you select safe wiring and protection for the circuit. Our Wire Size Calculator can help you determine the proper conductor gauge once you know the amperage, and a Voltage Drop Calculator ensures your wire run length won't cause excessive voltage loss.

If you need to work the other way around, converting amps and volts into watts, use our Amps to Watts Calculator. For conversions involving apparent power in kVA, our kVA to Amps Calculator handles the distinction between real and apparent power. You can also check your Amp Calculator for general current calculations, or use the Watts to Amps Calculator when your power is already expressed in watts.

For related projects like sizing a backup power system, our Generator Sizing Calculator uses similar electrical principles. And if you're estimating running costs alongside current draw, the Electricity Cost Calculator can translate your power consumption into dollars.


Frequently asked questions

What is the difference between kW and amps?

kW (kilowatts) measures electric power, which is how much energy a device uses per second. Amps (amperes) measure electric current, which is how much electricity flows through a wire. You need to know both the power and the voltage to convert between the two.

Why does the calculator ask for a power factor?

AC circuits do not always use power efficiently. The power factor is a number between 0.01 and 1 that shows how much of the power actually does useful work. Motors and compressors often have a power factor around 0.8 to 0.95. Without the power factor, the calculator cannot give you the correct amps for an AC circuit.

What power factor should I use if I do not know it?

Use 1 for purely resistive loads like heaters, light bulbs, and electric stoves. Use 0.8 as a safe general estimate for motors, pumps, and compressors. Check the device nameplate or data sheet for the exact value when possible.

What is the difference between line-to-line and line-to-neutral voltage?

Line-to-line voltage is measured between two hot wires in a three-phase system. Line-to-neutral voltage is measured between one hot wire and the neutral wire. Line-to-line voltage is higher by a factor of √3 (about 1.732). Pick the one that matches how you measured your voltage.

Can I use this calculator for watts instead of kilowatts?

Yes. Use the dropdown next to the power input and select W for watts or mW for milliwatts. The calculator converts everything to kilowatts internally and gives you the correct result in amps.

Why does three-phase use √3 in the formula?

Three-phase power uses three wires that carry current in a balanced pattern, each shifted by 120 degrees. When you measure voltage between two of those wires (line-to-line), the relationship between power and current includes a factor of √3 (about 1.732). This comes from how the three voltage waves combine.

How do I convert amps back to kW?

Reverse the formula. For DC: P (kW) = I (A) × V (V) ÷ 1,000. For single-phase AC: P (kW) = I × V × PF ÷ 1,000. For three-phase AC (line-to-line): P (kW) = I × V × PF × √3 ÷ 1,000.

Is this calculator accurate for real-world electrical work?

Yes, the calculator uses the standard electrical engineering formulas for DC, single-phase AC, and three-phase AC. However, real circuits can have voltage fluctuations, temperature effects, and varying power factors. Always verify your results with measured values and follow local electrical codes.

What does the chart below the result show?

The chart shows how the current in amps changes as voltage goes up or down while keeping your power constant. It helps you see that higher voltage means lower current for the same amount of power. The chart range goes from 25% to 200% of your entered voltage.

Can I enter decimal numbers or scientific notation?

Yes. The power and voltage fields accept decimals like 2.5 and scientific notation like 5e3 (which equals 5,000). This is useful for very small or very large values.

Why is my result showing a very high number of amps?

A high amp result usually means the voltage is very low compared to the power. Since amps = power ÷ voltage, a small voltage with a large power will produce a large current. Double-check that your voltage value and unit are correct.

Do I choose DC or AC for a solar panel system?

Solar panels produce DC power, so use the DC setting for the panel side. If you are calculating current after an inverter that converts DC to AC for your home, use AC Single Phase or AC Three Phase depending on your inverter output.

What is the result precision setting for?

It controls how many decimal places appear in your answer. Set it to 0 for a whole number or up to 8 for very precise results. A setting of 2 is good for most everyday electrical work.