NEC Conduit Fill Calculator
Calculate conduit fill per NEC Chapter 9 Tables 1, 4 & 5. Free to use — no account required.
Conduit & Wire Selection
PASS
Conduit fill is within NEC limits.
Each conductor area0.0097 in²
Total conductor area (3 × 0.0097 in²)0.0291 in²
Conduit internal area (100%)0.864 in²
Max fill allowed (40% — NEC Ch. 9 Table 1)0.3456 in²
Fill percentage used3.4%
0%40% max100%
NEC Table 1 Fill Rules (Chapter 9)
- • 1 conductor: 53% maximum fill
- • 2 conductors: 31% maximum fill
- • 3 or more conductors: 40% maximum fill
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This calculator uses NEC Chapter 9 Tables 4 & 5 values. Always verify with your local AHJ and the current NEC edition adopted in your jurisdiction.