A conduit can only hold a certain amount of wire before it gets too crowded. Overfilled conduit causes heat buildup and makes pulling wire very hard. The NEC limits fill to 40% of the conduit's inside area when you have 3 or more conductors. This tool calculates the total wire area and tells you if you're within that limit.
Tip: If your fill comes out over 40%, either go up one conduit size or remove a conductor run.
| Size | Type | Qty | Each (in²) | Total (in²) |
|---|
Per NEC Chapter 9, Table 1: max 40% fill for 3+ conductors, 31% for 2, 53% for 1.