12
12 AWG Wire Box Fill
12 AWG conductors are required for 20-amp circuits and kitchen/bathroom outlets.
2.25
cu.in. per conductor
36.9
mm3 per conductor
20A
Max Ampacity
Common Applications
20-amp circuits
Kitchen outlets
Bathroom GFCIs
Garage circuits
Box Capacity 12 AWG
Maximum number of conductors that fit in common electrical boxes (conductors only, not accounting for devices, clamps, or grounds).
| Box Type | Volume | Max 12 AWG* |
|---|---|---|
| 4" Square x 1-1/4" Deep | 18 cu.in. | 8 |
| 4" Square x 1-1/2" Deep | 21 cu.in. | 9 |
| 4" Square x 2-1/8" Deep | 30.3 cu.in. | 13 |
| 4-11/16" Square x 1-1/4" Deep | 25.5 cu.in. | 11 |
| 4-11/16" Square x 1-1/2" Deep | 29.5 cu.in. | 13 |
| 4-11/16" Square x 2-1/8" Deep | 42 cu.in. | 18 |
| Octagon Box 1-1/2" Deep | 15.5 cu.in. | 6 |
| 4" Octagon Box 1-1/2" Deep | 15.5 cu.in. | 6 |
| Octagon Box 2-1/8" Deep | 21.5 cu.in. | 9 |
| Single Gang Device Box 2-3/4" Deep | 14 cu.in. | 6 |
| Single Gang Device Box 18 cu.in. | 18 cu.in. | 8 |
| Single Gang Device Box 3-1/2" Deep | 18 cu.in. | 8 |