kVA to amps calculator

Preliminary estimate

Inputs

Calculation note

This converts apparent power to current. Equipment selection, conductor sizing, protection, and nameplate review remain separate.

Method

Three-phase amps = kVA x 1000 / (sqrt(3) x volts)

Single-phase amps = kVA x 1000 / volts

Unity-PF watts = kVA x 1000

MoreLess

Formula variables

  • kVA is apparent power.
  • Voltage is nominal circuit or equipment voltage.
  • Phase selects the current formula.
  • The current estimate still needs nameplate and project review before equipment decisions.

Assumptions

  • kVA is apparent power and does not need a power factor input.
  • Three-phase current uses the square-root-of-three relationship.
  • Single-phase current uses kVA x 1000 divided by voltage.
  • This calculator does not select equipment, conductors, breakers, transformers, or generators.

Examples

75 kVA transformer at 600 V. 75 kVA three-phase at 600 V estimates about 72.2 A.

12 kVA single-phase load. 12 kVA at 240 V single-phase estimates about 50 A.