What formula is used for DC circuits?

For DC circuits: V = (kW × 1000) / I. Power factor is always 1 for DC, so it is not needed.

What formula is used for single-phase AC?

For single-phase AC: V = (kW × 1000) / (I × PF), where PF is the power factor between 0 and 1.

What formula is used for three-phase AC?

For three-phase AC: V = (kW × 1000) / (√3 × I × PF). The result is the line-to-line (line) voltage.

What is power factor and what value should I use?

Power factor (PF) is the ratio of real power to apparent power, ranging from 0 to 1. Resistive loads (heaters, incandescent lights) have PF ≈ 1. Inductive motor loads typically have PF between 0.80 and 0.95. Check the equipment nameplate or use 0.9 as a reasonable default.

Does the result represent line voltage or phase voltage for three-phase?

The result is the line-to-line (line) voltage, which is the standard voltage rating used on three-phase equipment nameplates (e.g., 480 V, 415 V, 380 V).

Why do I get a very high voltage result?

Check that your current value is correct and that the power factor is not too low. A very small current or near-zero power factor produces a mathematically high voltage. Verify your inputs against the equipment nameplate.

How many volts is 20 kW?

Voltage is not fixed by power alone — it depends on current and circuit type. Example: 20 kW single-phase at 80 A with PF 0.9 gives V = 20000 / (80 × 0.9) ≈ 278 V. Enter your current and power factor above for the exact figure.

Kilowatts to Volts Calculator

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

Convert kilowatts to volts for DC, single-phase AC, and three-phase AC circuits given current and power factor.

Circuit Type

Formula V = (kW × 1000) / I

Power (P)

Current (I)

Enter power and current to calculate voltage

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Summary

Convert kilowatts to volts for DC, single-phase AC, and three-phase AC circuits given current and power factor.

How it works

Select the circuit type: DC, single-phase AC, or three-phase AC.
Enter the power in kilowatts (kW).
Enter the current in amperes (A).
For AC circuits, enter the power factor (0 to 1); DC defaults to 1.
The voltage is computed and displayed instantly.
Use the Copy button to copy the result to your clipboard.

Use cases

Determine the supply voltage for a known motor load and current draw.
Verify panel voltage requirements during electrical system design.
Cross-check generator output voltage against rated kW and current.
Quickly convert equipment nameplates from kW and amps to volts.
Size conductors and circuit breakers by confirming operating voltage.
Troubleshoot three-phase industrial machinery power specifications.
Educational reference for electrical engineering students.
Field checks during commissioning of AC and DC power systems.

Frequently Asked Questions

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