Board Foot Calculator
Lumber volume in board feet — thickness (in) × width (in) × length (ft) ÷ 12. Click any i for detail.
Lumber
Thickness (in)
i
Thickness
Nominal or actual thickness in inches (e.g. 1.5 for 2× stock). |
|
|---|---|
Width (in)
i
Width
Nominal or actual width in inches (e.g. 3.5 for 2×4). |
|
Length (ft)
i
Length
Piece length in feet. |
|
Piece count
i
Count
How many identical boards. |
How to use this calculator
- Enter thickness and width in inches.
- Enter length in feet and how many pieces.
- Read board feet for one piece and the lot.
- Match nominal vs actual size to how your yard prices.
Results explained
One board foot is 144 cubic inches of wood (12×12×1 in). Pricing may use nominal 2×4 sizes even when actual is 1.5×3.5.
Quick reference: board feet
Common dimensional lumber.
| Item | Detail |
|---|---|
| 2×4×8 (actual 1.5×3.5) | 3.5 bf |
| 2×6×8 (actual 1.5×5.5) | 5.5 bf |
| 1×12×8 (nominal 1×12) | 8 bf |
| 1 board foot | 144 in³ |
Hardwood is often sold by the board foot; framing lumber by the piece.
How the estimate is built
BF = (T_in × W_in × L_ft ÷ 12) × count.
Example scenario
Ten 8-ft 2×4s at actual 1.5×3.5 in = 35 board feet.
FAQ
Nominal or actual?
Yards differ. Use the size they bill, or measure the board.
Metric lumber?
Convert mm to inches first, or compute cubic meters instead.
Does this include waste?
No. Add 10–15% for cuts if you are buying a project lot.