Quick fill — common lumber sizes:
Add up to 4 different lumber sizes:
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Sources & Methodology
- 📖 Woodweb — Board Foot Measurement Reference
- 📖 USDA Forest Service — Timber Volume and Board Foot Standards
Formula: Board Feet = (Thickness" × Width" × Length') ÷ 12. Uses nominal dimensions as per standard lumber industry practice. Waste factor applied as a multiplier on the calculated board feet total.
How to Calculate Board Feet — The Formula Explained
If you've ever bought hardwood from a sawmill or specialty lumber dealer, you've dealt with board feet. It's how the industry measures and prices wood volume — and the formula is straightforward once you see it work on a real example.
The Board Foot Formula
Worked example: A 2×6 that is 8 feet long. (2 × 6 × 8) ÷ 12 = 8 board feet. If walnut costs $9/BF, this one piece costs $72. Ten pieces of the same = 80 board feet = $720.
Another example: Fifteen pieces of 1×4×10. (1 × 4 × 10) ÷ 12 = 3.33 BF per piece × 15 = 50 board feet total. At $5/BF: $250. With 15% waste: order 57.5 BF = $287.50 budget.
Nominal vs. Actual Dimensions — The Biggest Source of Confusion
A 2×4 does not measure 2 inches by 4 inches. After drying and planing, it measures 1.5" × 3.5". But board foot calculations use the nominal dimensions (the labeled size) — not the actual milled dimensions. This is standard across the entire industry.
So for a 2×6: you enter 2 and 6 even though the real piece is 1.5" × 5.5". Every lumber supplier calculates this way — it is not an error.
The Board Foot Shortcut for Common Sizes
When thickness × width = 12, board feet equal the length in feet directly. So a 2×6 (2×6=12), 1×12 (1×12=12), and 3×4 (3×4=12) all give board feet = length in feet. A 2×6×14 = exactly 14 board feet. Useful for quick mental math on the job site.
| Lumber Size | BF per 8 ft | BF per 10 ft | BF per 12 ft | BF per 16 ft |
|---|---|---|---|---|
| 1×4 | 2.67 | 3.33 | 4.00 | 5.33 |
| 1×6 | 4.00 | 5.00 | 6.00 | 8.00 |
| 1×8 | 5.33 | 6.67 | 8.00 | 10.67 |
| 1×12 | 8.00 | 10.00 | 12.00 | 16.00 |
| 2×4 | 5.33 | 6.67 | 8.00 | 10.67 |
| 2×6 | 8.00 | 10.00 | 12.00 | 16.00 |
| 2×8 | 10.67 | 13.33 | 16.00 | 21.33 |
| 2×10 | 13.33 | 16.67 | 20.00 | 26.67 |
| 4×4 | 10.67 | 13.33 | 16.00 | 21.33 |
| 4×6 | 16.00 | 20.00 | 24.00 | 32.00 |
Hardwood Lumber Prices by Species — What to Expect
Hardwood prices vary enormously by species, grade and where you buy. These ranges are typical for FAS (Firsts and Seconds) grade from specialty hardwood dealers in the US as of 2026:
| Species | Price Range per BF | Common Uses |
|---|---|---|
| Poplar | $3 – $5 | Painted furniture, shop fixtures |
| Alder | $3 – $6 | Cabinets, furniture, molding |
| Hard Maple | $5 – $8 | Butcher blocks, flooring, workbenches |
| Red Oak | $5 – $8 | Furniture, flooring, cabinets |
| White Oak | $6 – $10 | Barrels, boat building, furniture |
| Cherry | $7 – $12 | Fine furniture, cabinets, turning |
| Black Walnut | $8 – $15 | High-end furniture, gun stocks |
| Teak | $15 – $25 | Outdoor furniture, boat decks |
Board Feet vs. Linear Feet — Which Do You Need?
Linear feet just measures length — 12 inches, regardless of width or thickness. Home improvement stores often price dimensional framing lumber (2×4, 2×6) by the piece or linear foot. Hardwood dealers and sawmills price by the board foot.
If you're buying pine studs at Home Depot for framing, you're paying by the piece. If you're buying cherry or walnut for furniture, you're paying per board foot.
How to Check Your Lumber Order Against the Tally
When lumber arrives from a supplier with a tally sheet, verify each entry with the formula. Common shortcut: for a 2×6×14, since 2×6=12, the board feet = length = 14. For a 2×4×12: (2×4×12)÷12 = 8 board feet. Catching a tally error before the supplier leaves saves significant trouble.