Electrical Conduit Fill Calculator
NEC 40% fill for 3+ wires. Each 12 AWG THHN ~0.0133 sq in.
About this tool
Electrical Conduit Fill 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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