Volts to kVA Calculator

Enter voltage (V) and current (A) to calculate apparent power in kilovolt-amperes (kVA) for single-phase or three-phase AC circuits.

Input Values

V
A

Result

Enter voltage and current, then click Calculate.

Reference Formulas

Single-Phase

kVA = V × A / 1000

Example: 120 V × 10 A / 1000 = 1.2 kVA

Three-Phase

kVA = √3 × V × A / 1000

Example: 1.7321 × 480 V × 10 A / 1000 = 8.314 kVA

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Summary

Enter voltage (V) and current (A) to calculate apparent power in kilovolt-amperes (kVA) for single-phase or three-phase AC circuits.

How it works

  1. Select your circuit type: single-phase AC or three-phase AC.
  2. Enter the voltage in volts (V) — use line-to-line voltage for three-phase.
  3. Enter the current in amperes (A).
  4. Click Calculate to compute the apparent power in kVA.
  5. The result panel shows the kVA value, the formula applied, and a summary table.
  6. Click Reset to clear all fields and start over.

Use cases

  • Size transformers and generators for residential or commercial installations.
  • Determine UPS capacity requirements for servers and critical equipment.
  • Calculate apparent power for three-phase industrial motors and drives.
  • Specify circuit protection ratings and switchgear ampacity.
  • Compare single-phase and three-phase power for the same voltage and current.
  • Estimate panel board capacity when planning electrical service upgrades.
  • Convert nameplate voltage and current ratings to kVA for equipment procurement.
  • Verify that existing electrical infrastructure can support new load additions.

Frequently Asked Questions

Last updated: 2026-06-13 · Reviewed by Nham Vu