Circuit Breaker Sizing Calculator — NEC 125% Rule | WireStandard

Size circuit breakers correctly with NEC 125% continuous load rule. Add multiple loads, specify continuous vs non-continuous, get recommended standard breaker size.

Voltage (V)
Load List
Continuous
Non-Continuous
Remove
+ Add Load
Recommended Breaker Size
Continuous Load
Non-Continuous Load
Total Load
Adjusted Load (NEC 125%)
Out of table range — consult engineer

NEC 210.20: Continuous loads × 1.25. Standard breaker sizes: 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110, 125, 150, 175, 200A.