Electrical Breaker Sizing Calculator

Current
With 125% factor
Min breaker size

NEC 210.20: branch-circuit overcurrent protection ≥ 125% of continuous loads + 100% non-continuous.

About this tool

Electrical Breaker Sizing Calculator is a single-purpose utility on instant.tw, a free toolbox of calculators, converters, generators, and quick lookups. Everything works in your browser — nothing is uploaded, nothing is stored on a server unless explicitly noted.

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