Breaker Size Calculator
Calculate the correct circuit breaker size and wire pairing for a given load per NEC standards. Handles continuous, non-continuous, and motor loads.
Actual load current draw in amperes
Continuous loads run 3+ hours and require 125% sizing per NEC 210.20(A)
System voltage — residential is typically 120V or 240V
Copper is standard for branch circuits; aluminum for larger feeders
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