Conduit Fill Calculator
Calculate conduit size for wire combinations per NEC Chapter 9.
NEC Conduit Fill Rules
| Conductors | Max Fill % |
|---|---|
| 1 wire | 53% |
| 2 wires | 31% |
| 3+ wires | 40% |
Per NEC Chapter 9, Table 1. Different fill percentages prevent overheating and allow for wire pulling.