Conduit Fill Calculator — NEC 40% Limit | WireStandard
Calculate conduit fill percentage for EMT, IMC, RMC and PVC conduit. Check against NEC 40% fill limit with multiple wire sizes and counts.
- Conduit Type
- Conduit Size
- Wires
- Remove
- + Add Wire
- Fill Percentage
- Total Fill Area
- Conduit Internal Area
- Max wires ({{limit}}% fill, first AWG size)
- Cross-section view
- Conduit cross-section diagram
- {{type}} {{size}} conduit — wire layout (to scale)
- NEC 40% fill reference
- Overflow (does not fit)
Per NEC Chapter 9, Table 1: max 40% fill for 3+ conductors. Wire areas from NEC Chapter 9, Table 5 (THWN/THHN).