Board foot calculator — lumber volume & cost
A board foot is a 12 × 12 × 1-inch volume of lumber: thickness × width × length(ft) ÷ 12, using nominal dimensions. A 2×6×16 is 16 board feet. Enter boards below to total a stack and price it per board foot.
Your total
Board-foot math uses nominal sizes — a 2×6 counts as 2 × 6 even though it measures 1.5 × 5.5. Construction lumber at big-box stores is priced per piece instead.
Board feet in common lumber sizes
| Nominal size | Board feet |
|---|---|
| 1 × 6 × 8 ft | 4.0 |
| 2 × 4 × 8 ft | 5.33 |
| 2 × 6 × 8 ft | 8.0 |
| 2 × 6 × 16 ft | 16.0 |
| 2 × 8 × 12 ft | 16.0 |
| 2 × 10 × 12 ft | 20.0 |
| 2 × 12 × 16 ft | 32.0 |
| 4 × 4 × 8 ft | 10.67 |
Typical hardwood prices per board foot
| Species | Typical retail $/bf |
|---|---|
| Poplar | $3–5 |
| Red oak | $4–7 |
| Hard maple | $5–9 |
| Cherry | $6–10 |
| Black walnut | $9–15 |
| Select pine | $3–6 |
Ballpark retail ranges — grade (FAS vs #1 common), width, thickness, and region move hardwood prices substantially. Your dealer’s list governs.
How this calculator works
Board feet per piece = nominal thickness (in) × nominal width (in) × length (ft) ÷ 12; totals multiply by quantity. Cost = total board feet × your price per board foot. The nominal convention is the industry standard for both sawmills and hardwood dealers; quarter-thickness callouts (4/4, 8/4) map to nominal inches.
Common questions
How do you calculate board feet?
Thickness (in) × width (in) × length (ft) ÷ 12. One board foot is a 12 × 12 × 1-in volume of wood. A 2×6×16 is 2 × 6 × 16 ÷ 12 = 16 board feet.
How many board feet are in a 2×4×8?
2 × 4 × 8 ÷ 12 = 5.33 board feet. Note that construction lumber is usually priced per piece, not per board foot — board-foot pricing is the norm at hardwood dealers and sawmills.
Do board feet use nominal or actual dimensions?
Nominal. A “2×6” is counted as 2 in × 6 in even though it actually measures 1.5 × 5.5. Hardwood dealers use quarter thickness (4/4 = 1 in nominal, 8/4 = 2 in) the same way.
What does hardwood lumber cost per board foot?
Typical retail ranges: poplar $3–5, red oak $4–7, hard maple $5–9, cherry $6–10, black walnut $9–15 per board foot. Grade, width, thickness, and region move prices a lot — figures are ballpark retail, not quotes.
What does 4/4, 5/4, or 8/4 lumber mean?
Quarters of an inch of rough thickness: 4/4 (“four-quarter”) = 1 in, 5/4 = 1.25 in, 8/4 = 2 in. A dealer selling 8/4 walnut charges the 2-in nominal thickness in the board-foot math even after surfacing takes it to ~1.75 in.