Generator Sizing Tool

Generator Watts to Amps Calculator

Convert generator wattage to output amps for load planning. A 5000W generator at 240V split-phase provides about 20.8A per leg. Use this to plan which appliances you can run simultaneously during a power outage.

Conversion direction

Electrical system

PowerWVoltageV

Quick voltage presets

Calculated result1000 W · 120 V · DC

8.333 A

Formula usedI = P / V

Custom voltage is always supported.

Formulas Used

DCI = P / V

No power factor needed for DC circuits.

AC 1φI = P / (V × PF)

Single-phase AC — multiply voltage by power factor.

AC 3φI = P / (√3 × V × PF)

Three-phase AC — divide by √3 ≈ 1.732.

Frequently Asked Questions

How many amps does a 5000W generator produce?

At 240V (split phase, 120V per leg): 5000 / 240 = 20.8A total, or about 20.8A per 120V leg. At 120V only: 5000 / 120 = 41.7A.

How many amps does a 10000W generator produce?

At 240V: 10000 / 240 = 41.7A total. This is enough for a 40A transfer switch and most whole-home essential loads.