Circuit Breaker Size Calculator

Find the right breaker and wire size per NEC guidelines

Breaker & Wire Size Chart

NEC standard breaker-to-wire matching (copper, 60C)

Breaker (A)Min Wire (AWG Cu)Max Load (W @120V)Max Load (W @240V)
15141,4402,880
20121,9203,840
30102,8805,760
4083,8407,680
5064,8009,600
6045,76011,520
10019,60019,200
2002/019,20038,400
NEC 80% Rule: Continuous loads must not exceed 80% of the breaker rating. Values above reflect 80% safe load.