CutlistNominal and actual lumber sizes
A nominal 2 × 4 is not normally 2 inches by 4 inches. Check the actual dimensions for the stock you buy.
| Nominal size (in) | Actual thickness × width (in) |
|---|---|
| 1 × 4 | ¾ × 3½ |
| 1 × 6 | ¾ × 5½ |
| 2 × 4 | 1½ × 3½ |
| 2 × 6 | 1½ × 5½ |
| 2 × 8 | 1½ × 7¼ |
| 4 × 4 | 3½ × 3½ |
How the calculation works
The table shows common nominal and actual dimensions for surfaced dimensional lumber in inches. A label such as 2 × 4 is a size name; it is not a substitute for measuring the stock you have. Rough-sawn, green and specialty material can differ.
For a common surfaced 2 × 4, use the measured 1½ × 3½ inch cross-section when appropriate. Entering 2 × 4 instead increases the calculated volume. Use the supplier’s actual dimensions when they differ from this reference.
Related tools
Board foot calculator
Enter actual board dimensions to total the volume, waste allowance and optional cost.
02Cubic feet of lumber
Calculate CFT from actual dimensions, with the same inputs available in metric or inches.
03Log volume and log rules
Choose a geometric volume formula or a board-foot log rule. These measure different things; use the method agreed with your supplier.