Lumber Nominal vs Actual
Nominal lumber dimensions vs actual surfaced dimensions (inches).
| Nominal | Thickness | Width |
|---|---|---|
| 1x2 | 0.75 | 1.5 |
| 1x3 | 0.75 | 2.5 |
| 1x4 | 0.75 | 3.5 |
| 1x6 | 0.75 | 5.5 |
| 1x8 | 0.75 | 7.25 |
| 1x10 | 0.75 | 9.25 |
| 1x12 | 0.75 | 11.25 |
| 2x2 | 1.5 | 1.5 |
| 2x3 | 1.5 | 2.5 |
| 2x4 | 1.5 | 3.5 |
| 2x6 | 1.5 | 5.5 |
| 2x8 | 1.5 | 7.25 |
| 2x10 | 1.5 | 9.25 |
| 2x12 | 1.5 | 11.25 |
| 4x4 | 3.5 | 3.5 |
| 4x6 | 3.5 | 5.5 |
| 6x6 | 5.5 | 5.5 |
About this lookup
- Why is 2x4 not 2 inches by 4 inches?
- Nominal sizes are pre-surfacing. After planing and drying, the actual dimensions shrink.
- When did the standards change?
- The current standard dimensions have been used since the 1960s in the US lumber industry.