Calculate required junction box volume per NEC Article 314. Enter wire count, gauge (AWG), and conduit entries to get the correct electrical box size for safe installations.
Required Box Volume
Recommended Box Size
Box Visualization
Junction box sizing is based on the National Electrical Code (NEC) requirements. The calculator determines the minimum box volume needed based on the number and gauge of wires, plus additional space for connections and conduit entries. A 25% safety factor is added to ensure adequate space.
| Wire Gauge (AWG) | Volume Per Wire |
|---|---|
| 2 AWG | 8 cubic inches |
| 4 AWG | 6 cubic inches |
| 6 AWG | 5 cubic inches |
| 8 AWG | 3 cubic inches |
| 10 AWG | 2.5 cubic inches |
| 12 AWG | 2.25 cubic inches |
| 14 AWG | 2 cubic inches |
| 1/0 AWG | 10 cubic inches |
| 2/0 AWG | 11 cubic inches |
| 3/0 AWG | 12 cubic inches |
| 4/0 AWG | 13 cubic inches |
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