Lumber Calculator
Board Feet, Not Linear Feet, Is How Lumber Is Priced
A 2x4 and a 2x12 of the same length cost very different amounts, because lumber is priced by volume, not by how many linear feet you're buying. Board feet packs thickness, width, and length into a single number that lets you compare a stack of narrow studs against a handful of wide beams on equal footing.
The Formula
Total Board Feet = Board Feet per Board × Quantity
One board foot is the volume of a board 1 inch thick, 12 inches wide, and 1 foot long. The calculator multiplies a board's nominal thickness and width in inches by its length in feet, then divides by 12 to convert that into board feet, and multiplies by however many identical boards you're buying to get the total.
Where This Calculation Matters
- Framing takeoffs — lumber yards quote per board foot for dimensional lumber, so converting a cut list into board feet is how you get a comparable price across different board sizes.
- Hardwood and specialty lumber — board foot pricing is standard for hardwood, where boards often come in random, non-standard widths and lengths.
- Comparing suppliers — a per-board-foot price lets you compare a quote from one yard against another even if they've priced individual pieces differently.
Board Feet by Common Dimensional Lumber
| Board | Board Feet (1 board) |
|---|---|
| 2x6, 8 ft | 8.00 |
| 2x8, 10 ft | 13.33 |
| 2x4, 12 ft (×10 boards) | 80.00 total |
Nominal lumber dimensions (like "2x6") are used here, which is standard trade practice even though actual milled dimensions are slightly smaller.
How to Use This Calculator
- Enter the board's Thickness and Width in inches (nominal size, e.g. 2 and 6 for a 2x6).
- Enter the Length in feet.
- Enter the Quantity of identical boards you need.
- Select Calculate to see the total board feet.
Related Calculations
Framing a roof with that lumber? The Roofing Calculator tells you how much surface material to buy, and the Construction Cost Calculator can roll board feet into a full project budget.