Three-Phase Power Calculator

Calculate three-phase power, current, and power factor.

V
A
Guides & Reference

How It Works

P = root(3) x V x I x PF. Root(3) = 1.732 accounts for 120-degree phase offset. More efficient than single-phase for large loads.

Formula

P = sqrt(3) x V x I x PF

Quick Reference

Common calculations — results you can verify instantly.

480V, 50A, PF=0.85

1.732×480×50×0.85

35.3 kW

208V, 30A, PF=0.90

1.732×208×30×0.90

9.73 kW

Single vs 3-phase

Same voltage and current

3-phase is 1.73× more power

Tips & Shortcuts

Most industrial motors use 3-phase power.

208V line-to-line commercial. 480V industrial.

Common Mistakes

Using single-phase formula for 3-phase

3-phase: P = 1.732 x V x I x PF. Not V x I x PF.

Confusing line and phase voltage

Line voltage = root(3) x phase voltage.

Frequently Asked Questions

More efficient, constant power delivery, smaller conductors.

208V commercial. 480V industrial.

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