Add multiple rows of different lumber sizes. The tool automatically totals board feet and cost.
| Thick | Width | Length | Unit(T/W) | Unit(L) | Qty | $/BF | BF | Cost |
|---|
Select a nominal lumber size to auto-fill actual dimensions and calculate board feet.
A board foot (BF) is the standard unit of measurement for lumber in North America. Whether you're a professional woodworker, DIY enthusiast, or construction contractor, accurately calculating board feet is essential for estimating material needs and costs.
When thickness and width are in inches and length is in feet:
Board Feet = (Thickness[in] × Width[in] × Length[ft]) / 12
When all dimensions are in inches:
Board Feet = (Thickness[in] × Width[in] × Length[in]) / 144
| Unit | Convert to Inches |
|---|---|
| 1 Foot (ft) | 12 in |
| 1 Millimeter (mm) | 0.03937 in |
| 1 Centimeter (cm) | 0.3937 in |
| 1 Meter (m) | 39.37 in |
| Nominal | Actual Thickness (in) | Actual Width (in) |
|---|---|---|
| 1×2 | 0.75 | 1.5 |
| 1×4 | 0.75 | 3.5 |
| 1×6 | 0.75 | 5.5 |
| 1×8 | 0.75 | 7.25 |
| 1×10 | 0.75 | 9.25 |
| 1×12 | 0.75 | 11.25 |
| 2×2 | 1.5 | 1.5 |
| 2×4 | 1.5 | 3.5 |
| 2×6 | 1.5 | 5.5 |
| 2×8 | 1.5 | 7.25 |
| 2×10 | 1.5 | 9.25 |
| 2×12 | 1.5 | 11.25 |
| 4×4 | 3.5 | 3.5 |
| 4×6 | 3.5 | 5.5 |
| 6×6 | 5.5 | 5.5 |
A board foot (BF) is the standard unit of measurement for lumber in North America. One board foot equals 12 inches × 12 inches × 1 inch of wood volume. The formula is: Board Feet = (Thickness[in] × Width[in] × Length[ft]) / 12. Lumber is typically priced and sold by the board foot.
Nominal size is the size of lumber when cut at the sawmill (e.g., 2×4), while actual size is the real dimension after drying and planing (a 2×4 is actually 1.5" × 3.5"). Lumber is sold by nominal size names, but board foot calculations should use actual dimensions. This calculator includes a built-in nominal-to-actual size lookup table.
For boards of the same size, calculate the board feet of one piece and multiply by the quantity. For multiple batches of different sizes, use the Batch Calculation mode — add each specification as a row, and the tool automatically sums up total board feet and total cost.
One board foot equals 1/12 of a cubic foot (approximately 0.0833 cubic feet). Therefore, 1 cubic foot = 12 board feet. In metric units, 1 board foot ≈ 0.00236 cubic meters ≈ 2,359.7 cubic centimeters. Board feet are primarily used in North America; Europe and Asia typically use cubic meters.
Lumber is typically sold by the board foot. Enter the price per board foot ($/BF) in the calculator, and it will compute total cost = board feet × unit price. Prices vary widely by species: pine runs about $2-5/BF, oak $4-8/BF, and walnut $8-15/BF. Check with your local supplier for current pricing.