What is the formula for DC circuits?

For DC: P(kW) = V(V) × I(A) / 1000. Multiply voltage by current and divide by 1000 to convert watts to kilowatts.

What is the formula for single-phase AC circuits?

For single-phase AC: P(kW) = V(V) × I(A) × PF / 1000. The power factor (PF) accounts for the phase difference between voltage and current waveforms.

What is the formula for three-phase AC circuits?

For three-phase AC: P(kW) = √3 × V(V) × I(A) × PF / 1000. The √3 factor (≈ 1.7321) accounts for the three-phase relationship, and V is the line-to-line voltage.

What is power factor and why does it matter?

Power factor (PF) is a number between 0 and 1 that represents how effectively electrical power is being used. Purely resistive loads (heaters, incandescent bulbs) have PF = 1. Inductive loads like motors typically have PF between 0.7 and 0.95. A lower PF means more current is needed to deliver the same real power.

Why is there no power factor for DC circuits?

DC circuits carry constant current with no frequency, so there is no phase shift between voltage and current. Power factor is only relevant in AC circuits where reactive loads cause the current and voltage waveforms to become out of phase.

What is the difference between kW and kVA?

kW (kilowatts) is real power — the actual energy consumed per unit time. kVA (kilovolt-amperes) is apparent power, which equals V × I / 1000 without accounting for power factor. They are related by: kW = kVA × PF. For resistive loads and DC circuits, kW equals kVA.

Volts to Kilowatts Calculator

Name: Volts to Kilowatts Calculator
Availability: InStock
Author: Nham Vu

Enter voltage, current, and power factor (AC only) to convert volts to kilowatts for DC or AC circuits.

Circuit Parameters

Circuit Type

Voltage (V)

Current (A)

Result

Enter values and press Calculate

Formula Reference

DC Circuits

kW = V × A / 1000

Single-Phase AC

kW = V × A × PF / 1000

Three-Phase AC

kW = √3 × V × A × PF / 1000

Result copied!

Summary

Enter voltage, current, and power factor (AC only) to convert volts to kilowatts for DC or AC circuits.

How it works

Select your circuit type: DC, single-phase AC, or three-phase AC.
Enter the voltage in volts (V).
Enter the current in amperes (A).
For AC circuits, enter the power factor (a value between 0 and 1).
Click Calculate to see the result in kilowatts (kW).
Use Reset to clear all fields and start a new calculation.

Use cases

Determine the real power output of a generator given its rated voltage and current.
Size wiring and circuit breakers based on voltage and expected load current.
Estimate energy consumption of industrial motors in kilowatts.
Verify nameplate power ratings on electrical equipment.
Calculate power draw of three-phase HVAC systems and compressors.
Plan solar inverter capacity by converting panel voltage and current to kW.
Convert EV charger voltage and current ratings to power output.
Troubleshoot electrical systems by cross-checking measured voltage and current against rated power.

Frequently Asked Questions

Last updated: 2026-06-14 · Reviewed by Nham Vu