Calculate board feet, linear feet, and total lumber or timber needed for framing and woodworking projects.
This lumber calculator (also useful as a timber or board-foot calculator) works out total length, board feet and an estimated cost from the number of pieces and their size. It's handy for framing, decking and joinery whether you buy by the board foot (US) or the linear/lineal metre (UK), in metric or imperial.
| Nominal (US) | Actual size |
|---|---|
| 2×4 | 1.5 × 3.5 in (38 × 89 mm) |
| 2×6 | 1.5 × 5.5 in (38 × 140 mm) |
| 4×4 | 3.5 × 3.5 in (89 × 89 mm) |
Board feet = (thickness in × width in × length ft) ÷ 12. Ten 2×4 boards at 8 ft each = (2 × 4 × 8 ÷ 12) × 10 = 53.3 board feet.
A board foot is 1 inch thick × 12 inches wide × 12 inches long (144 cubic inches). It’s the standard unit for buying lumber.
Divide total board feet by (thickness × width / 12). For a 2×6, divide by 1 (since 2×6/12 = 1).
A “2×4” is actually 1.5×3.5 inches. A “2×6” is 1.5×5.5 inches. This is due to drying and planing.
A 2 × 4 that is 8 ft long contains 5.33 board feet (2 × 4 × 8 ÷ 12). The calculator works this out for any dimensions you enter.
You need the board width and thickness as well as length. The calculator works out board feet from the dimensions you enter.
