Measure the boards.
See the working.

A volume measure, not a board shape

One board foot is 144 cubic inches of lumber. The familiar example is a board one inch thick, twelve inches wide and one foot long, but the unit is not restricted to that shape. A two-inch-thick board can reach one board foot with half as much face area; a thinner board needs proportionally more area. BoardFoot Bench calculates from the dimensions you provide, so the result documents the piece in front of you rather than guessing from a product name.

With thickness and width in inches and length in feet, the working formula is thickness × width × length × quantity ÷ 12. For the default example, 1.25 × 7.5 × 8 ÷ 12 equals 6.25 board feet per piece. Three pieces equal 18.75 board feet. The result panel keeps the per-piece value, input basis and rounding beside the total so the answer can be checked or copied without losing its meaning.

Label the dimensions before doing the arithmetic

Actual dimensions describe physical measurements. Nominal dimensions are trade names or reference sizes and may not match the dressed board. Both can be useful, but they answer different questions. A supplier’s hardwood tally may follow a documented trade convention, while a workshop cut list may need measured finished dimensions. This site does not silently convert a typed nominal size into a presumed actual size.

If you need to compare the two, use the nominal versus actual calculator. It displays both volumes and the difference while leaving every dimension editable. The accompanying common dressed softwood table is a reference only: it does not automatically govern rough hardwood, reclaimed material, specialty products or every supplier’s tolerance.

Keep measurement, allowance and money separate

A mixed lumber order should preserve each size as a separate row. The lumber tally calculator totals valid rows without disguising an error as zero. Add a row for every distinct thickness, width, length or quantity, use labels that make sense on the invoice, and confirm whether the figures are actual or nominal. The sum uses unrounded row values so repeated display rounding does not drift into the total.

After the volume is known, the price calculator can add a stated overage and rate. Base quantity, allowance quantity, order quantity, material subtotal, sales tax and total remain separate. That structure makes it clear whether a percentage changes the amount of wood purchased or the amount of money due. Prices are typed by the visitor; BoardFoot Bench does not infer market rates, species premiums, delivery charges or currency conversion.

Change units without changing the quantity

The conversion workbench covers board feet, cubic inches, cubic feet, cubic metres and MBF. One board foot is 144 cubic inches and one twelfth of a cubic foot. The metric production factor is 0.002359737216 cubic metres per board foot, derived from the exact international inch. The retained NIST reference prints fewer decimal places, and the methodology distinguishes that published table value from the longer derived value.

Square feet cannot become board feet until thickness is supplied because square feet measures area and board feet measures volume. At one inch thick, one square foot corresponds to one board foot. At three-quarter inch, 120 square feet corresponds to 90 board feet. MBF is explicitly defined here as 1,000 board feet; when an abbreviation is used in a commercial document, confirm the other party’s convention.

Use a named rule and its supported table

Doyle, Scribner and International ¼-inch are log scaling rules. They estimate potential lumber recovery and can disagree even when applied to the same log. They are not alternate ways to measure the log’s physical volume. A reproducible result needs the exact named rule, small-end diameter inside bark, log length, supported table or equation, gross estimate and any separate deduction.

The public Doyle and International ¼-inch tools use retained USDA Forest Service SOLVE table values for diameters from 8 through 26 inches and lengths of 8, 10, 12, 14 or 16 feet. Inputs outside that reviewed set fail closed. Scribner remains held because authoritative and regional publications describe materially different variants and rounding. The site explains that boundary instead of displaying a number under an underspecified label.

What a board-foot total cannot tell you

Volume alone does not establish lumber grade, species performance, moisture condition, structural capacity, defect allowance, kerf loss or finished yield. Confirm those matters separately with the supplier, applicable standard or qualified professional. For an auditable record, keep the entered dimensions and units, actual-or-nominal basis, quantity, calculation trail, rounding rule and review date with the total.