Loan Board Foot Estimator
Hardwood is sold by a unit you cannot see: the board foot. Enter the board dimensions the way the yard writes them and get board feet per board, for the pile, and priced at your rate.
Use the nominal dimensions the lumber is sold by — a "2×6" that measures 1.5 × 5.5 in is still billed as 2×6 in board-foot pricing at most yards. Rough lumber is sold by its rough (pre-surfacing) thickness: 4/4 stock is 1 in on the tally.
How it works
A board foot is 144 cubic inches of wood — a 12 × 12 × 1 in slab. The formula is thickness (in) × width (in) × length (ft) ÷ 12: a 2×6, 8 ft long is 2 × 6 × 8 ÷ 12 = 8 board feet. Yards tally rough lumber by these nominal dimensions, then price the pile at the species rate per board foot. The trick that catches newcomers: surfacing removes wood but not board feet — a 4/4 board planed to ¾ in still bills as a full board foot per foot of 12-in width.
Formula & worked example
Formula: Board feet per board = thickness (in) × width (in) × length (ft) ÷ 12. Total = per-board × quantity; cost = total × price per board foot. Dimensions are the nominal (sold-by) sizes, matching how yards tally rough lumber.
Worked example: A 2×6, 8 ft long: 2 × 6 × 8 ÷ 12 = 8.00 board feet. Ten boards = 80.00 board feet, which at $6.50 per board foot is $520.00 — the tally math a hardwood yard does on the invoice.
When to use this
- Buying hardwood at a lumber yard that prices by the board foot.
- Checking a yard's tally sheet against your own count before paying.
- Costing a furniture or cabinet project's lumber from a cut list.
- Comparing species prices honestly — per board foot is the only fair unit.
How to use it, step by step
- List each board size in your cut list: thickness, width, length.
- Enter the quantity of identical boards.
- Add your yard's price per board foot for the species and grade.
- Run each size separately and sum the totals for the project tally.
- Add 20–30% quantity for furniture work — grain selection and defects are real.
What the inputs mean
| Input | What it is | Typical values |
|---|---|---|
| Thickness & width | Nominal sold-by dimensions in inches | 4/4 (1 in) and 8/4 (2 in) common |
| Length | Board length in feet | 6–12 ft typical boards |
| Quantity | Identical boards | From your cut list |
| Price per board foot | Yard's rate for the species | $3–$15 domestic hardwoods |
Another worked example
A tabletop glue-up: six boards of 1×12, each 10 ft — 10.00 board feet apiece, 60 total. At $8.00 per board foot for the species chosen, the top's lumber is $480.00 before legs and aprons — the number that decides whether the project starts this month.
Frequently asked questions
How many board feet is a 2×6, 8 feet long?
2 × 6 × 8 ÷ 12 = 8 board feet. Ten of them make 80 board feet — at $6.50 per board foot, a $520 pile. The same math in reverse sizes any board: divide the board feet you need by the per-board figure.
What is a board foot, in plain terms?
The volume of a board 1 ft long, 1 ft wide and 1 in thick — 144 cubic inches. It is a volume unit wearing an area costume, which is why thickness counts in the formula even though the board looks flat.
Why did the yard charge me for more wood than I took home?
Board feet are tallied on rough, unsurfaced dimensions. A 4/4 board that leaves the planer at ¾ in thick was still a full inch when it was measured and priced. It is not a scam — it is the industry convention since before power planers — but it surprises every first-time hardwood buyer.
How much extra lumber should I buy for a project?
Furniture and cabinet work: 20–30% over the finished board footage for grain selection, defects and milling loss. Rough framing-style work can run 10–15%. The estimator prices the exact tally; add your margin to the quantity before you go.
What does hardwood cost per board foot?
Common domestic species (red oak, poplar, soft maple) often run $3–$7 per board foot; walnut and white oak $8–$15; exotics well beyond. Prices move with region and grade — the price field here takes whatever your yard quoted.
🪜 Building stairs from that lumber?
Stringers and treads start with the geometry: the Stair Estimator works out risers, treads, run and stringer length from your floor-to-floor height.
What does 4/4 and 8/4 mean at the lumber yard?
Thickness in quarter-inches, rough: 4/4 is 1-in rough stock (surfaces to about ¾ in), 8/4 is 2-in (surfaces to about 1¾ in). Board feet are tallied on the rough figure, which is why a '1-inch' board from the yard measures less at home.
How do I estimate a whole project's lumber?
Total the finished board footage of every part from the cut list, then add the waste factor for the work type — 15% for simple, 25% for furniture with grain matching. Run each distinct board size through the estimator and add the runs.