Board Foot Calculator
Calculate lumber volume in board feet (BF) from thickness × width × length. Formula: BF = T × W × L / 12 (T and W in inches, L in feet).
Common lumber board foot reference
| Nominal size | BF per linear ft | 8 ft board | 16 ft board |
|---|---|---|---|
| 1 × 4 | 0.33 BF/ft | 2.67 BF | 5.33 BF |
| 1 × 6 | 0.50 BF/ft | 4.00 BF | 8.00 BF |
| 1 × 8 | 0.67 BF/ft | 5.33 BF | 10.67 BF |
| 1 × 10 | 0.83 BF/ft | 6.67 BF | 13.33 BF |
| 2 × 4 | 0.67 BF/ft | 5.33 BF | 10.67 BF |
| 2 × 6 | 1.00 BF/ft | 8.00 BF | 16.00 BF |
| 2 × 8 | 1.33 BF/ft | 10.67 BF | 21.33 BF |
| 2 × 10 | 1.67 BF/ft | 13.33 BF | 26.67 BF |
FAQs
What is a board foot?
A board foot is a unit of lumber volume equal to 144 cubic inches (12" × 12" × 1"). It measures hardwood and other dimensional lumber. Formula: Board feet = (Thickness × Width × Length) / 144, where thickness and width are in inches and length is in feet. (Or all in inches, divide by 144.)
How do I calculate board feet?
Use the formula: BF = (T × W × L) / 12, where T = thickness in inches, W = width in inches, L = length in feet. Example: 1" × 8" × 10' board = (1 × 8 × 10) / 12 = 6.67 board feet. For multiple boards, multiply by the number of boards.
What's the difference between board foot and square foot?
Board foot measures VOLUME (with thickness); square foot measures AREA (no thickness). A 2" × 4" × 8' board = 5.33 board feet (volume) but covers 4 sq ft (area) of wall when used flat. Board feet matters for lumber pricing; square feet matters for room coverage.
Why is lumber sold in board feet?
Hardwood lumber prices vary by species AND thickness, so volume (board feet) is the natural unit. Pine and softwoods are sometimes sold by board feet or by 'linear foot' (just length). 1,000 board feet = MBF, the standard wholesale unit.
How much does lumber cost per board foot?
Highly varies by species: Pine: $3-$5/BF. Oak: $4-$8/BF. Maple: $5-$10/BF. Walnut: $10-$18/BF. Cherry: $8-$15/BF. Mahogany: $12-$25/BF. Exotic hardwoods: $20-$50+/BF. Prices vary by grade (FAS, Select, #1 Common) and dimensions. Buy thicker stock for projects requiring resawing.
What's the difference between nominal and actual lumber sizes?
Nominal: the size you ASK for at the lumberyard ('2x4'). Actual: what you ACTUALLY get after kiln-drying and planing ('1.5" × 3.5"'). For board foot calculations, always use NOMINAL dimensions — that's how lumber is sold and priced. 2x4 × 8' is 5.33 BF nominal, regardless of actual dimensions.