liminfoBoard Foot Calculator
Free web tool: Board Foot Calculator
Per Piece
4.00
BF
Total BF
4.00
Volume (m³)
0.0094
About Board Foot Calculator
The Board Foot Calculator is a lumber volume tool used by woodworkers, carpenters, sawmill operators, and timber buyers to measure and price wood. A board foot (BF) is the standard unit of lumber volume in North America, defined as a piece of wood that is 1 inch thick, 12 inches wide, and 12 inches long — equivalent to 144 cubic inches or approximately 2,360 cm³. The formula is: Board Feet = (Thickness in inches × Width in inches × Length in feet) ÷ 12.
Lumber is priced and sold in board feet because it normalizes volume across boards of different dimensions. A hardwood dealer selling 4/4 walnut at $12 per BF is quoting the price for each 144 cubic-inch unit of wood. This calculator is essential when purchasing lumber for furniture making, cabinet building, flooring, decking, or structural timber — any situation where you need to compare costs across different board sizes or determine how much wood to buy for a project.
This tool accepts thickness in inches, width in inches, length in feet, and quantity. It computes board feet per individual piece and total board feet for the entire order. A cubic meter conversion (1 BF = 0.002360 m³) is also provided for international buyers. Optionally enter a price per board foot to calculate the total material cost. All calculations happen instantly in your browser with no registration required.
Key Features
- Calculates board feet per piece using the formula: (T × W × L) ÷ 12
- Multiplies per-piece BF by quantity to give total board feet for the order
- Converts total board feet to cubic meters (m³) for international reference
- Optional price-per-BF input to calculate total lumber cost instantly
- Four-field layout: thickness (in), width (in), length (ft), and quantity
- Real-time recalculation as any input value changes
- 100% client-side processing — measurements and costs never leave your browser
- Dark mode support and responsive design for use in workshops or on job sites
Frequently Asked Questions
What is a board foot?
A board foot is the standard unit of lumber volume used in North America. It equals 144 cubic inches — the volume of a board 1 inch thick, 12 inches wide, and 12 inches long. It is abbreviated BF or bf and is used to price and sell dimensional lumber, hardwood, and timber.
What is the board foot formula?
Board Feet = (Thickness in inches × Width in inches × Length in feet) ÷ 12. For example, a board that is 2 inches thick, 6 inches wide, and 8 feet long contains (2 × 6 × 8) ÷ 12 = 8 board feet.
Why is lumber sold in board feet instead of by linear foot?
Linear feet measure only length, ignoring thickness and width. Board feet account for all three dimensions, giving a true volume measurement. This allows fair pricing comparison between a thin 1×4 and a thick 4×4 of the same length, since the thicker board contains far more wood.
What does 4/4 lumber mean?
4/4 (pronounced "four quarter") means the rough-sawn thickness is 4 quarter-inches, or 1 inch. Hardwood lumber is commonly sold in quarter-inch increments: 4/4 (1 in), 5/4 (1.25 in), 6/4 (1.5 in), 8/4 (2 in), etc. Enter the rough thickness in the calculator for accurate board foot counts.
How do I calculate the cost of a lumber order?
Enter thickness, width, and length to get total board feet, then enter the price per board foot from your supplier. The calculator multiplies total BF by the price per BF to give you the total material cost. For example, 50 BF of walnut at $15/BF = $750.
How many board feet are in a cubic meter?
One board foot equals approximately 0.002360 m³, so 1 cubic meter equals approximately 424 board feet. This conversion is useful when comparing prices between North American suppliers (who quote in BF) and international suppliers (who quote in m³).
Can I use this calculator for rough-sawn vs. finished lumber?
Yes. Board feet measure gross rough volume before milling, which is how sawmills and hardwood dealers price wood. Enter the actual rough dimensions. After surfacing (planing and jointing), the finished dimensions will be slightly smaller, but the price was calculated on the rough board foot count.
How accurate is board foot measurement for irregular boards?
For boards with consistent dimensions, the formula is exact. For live-edge slabs, tapered boards, or irregular shapes, you can use average width measurements. Many sawmills measure the narrowest and widest widths and average them when computing board feet for oddly shaped pieces.