Board Foot & Lumber
Board feet for a lumber list from nominal sizes, each item’s dressed (actual) size from the American Softwood Lumber Standard, linear feet, and cost.
A priced lumber tally you can hand to a yard — board feet per item and in total, the actual dressed dimensions, and the dressed volume kept separate from the nominal count.
Example: Ten 2 × 4 × 8 ft studs are 53.3 board feet; each is dressed 1½ × 3½ in, and at $0.85 per board foot the lot is $45.33.
Nominal for the tally,
dressed for the fit.
Why a 2 × 4 counts as 2 × 4 but measures 1½ × 3½, and where each figure comes from.
Board measure
A board foot is the unit of lumber measure: nominal thickness (inches) × nominal width (inches) × length (feet) ÷ 12 — the definition in the American Softwood Lumber Standard (DOC PS 20-25, section 2.2). It is counted on nominal sizes by industry practice, so a 2 × 4 × 8 ft is 5⅓ board feet whatever it was dressed to. 5/4 stock counts as 1¼ in thick. Linear feet are simply length × quantity.
Dressed sizes
The actual size of standard items comes from Table 3 of PS 20-25 (dry minimum-dressed sizes): 1 in → ¾ in, 2 in → 1½ in, 4 in → 3½ in, 6 in → 5½ in, 8 in → 7¼ in, 12 in → 11¼ in, and so on. Timbers (5 in or more in the least dimension) are ½ in under nominal at 5–6 in, ¾ in under at 7–15 in, and 1 in under at 16 in and over in the 2025 edition — suppliers may still follow the earlier ½-in rule, so check the invoice. PS 20 is a U.S. Department of Commerce publication; the table in this utility was transcribed from it and names the edition and date.
What the numbers do not say
Board feet are not a volume: PS 20's own appendix warns against converting them to cubic metres. The dressed volume shown here is a separate figure from the dressed sizes, and it is not shown at all for a size the standard does not list. Green (unseasoned) sizes, hardwood grading rules, and waste for cutting are outside this tally. Prices are whatever you enter. Inputs stay in your browser; the same four anonymous usage counts as the rest of the site apply.