Board Feet Calculator — Lumber Volume & Cost Estimator
Calculate board feet of lumber for any thickness, width, and length. Estimate total volume and project cost with optional price-per-board-foot input.
How to Use This Calculator
- Enter the thickness, width, and length of one board (use actual dimensions, not nominal)
- Enter how many boards you need
- Optionally enter the price per board foot to calculate total cost
- Click "Calculate Board Feet" to see your results
How the Calculation Works
board_feet = (thickness_in × width_in × length_ft) / 12
total_board_feet = board_feet × quantity
total_cost = total_board_feet × price_per_bf // if price entered Board feet is the standard unit for measuring hardwood lumber volume. The formula multiplies thickness (in inches) by width (in inches) by length (in feet), then divides by 12. This gives you board feet per piece. Multiply by quantity for your total, then by price per board foot for cost.
Variables:
- thickness_in: Thickness of the board in inches (use actual, not nominal)
- width_in: Width of the board in inches (use actual, not nominal)
- length_ft: Length of the board in feet
- quantity: Number of identical boards
- price_per_bf: Optional: cost per board foot in dollars
Pro Tips
- Board feet is a volume measurement: 1 board foot = 144 cubic inches of wood
- Dimensional lumber (2×4, 2×6) is sold by linear foot, not board feet — use this for hardwoods and specialty lumber
- Hardwood dealers quote prices per board foot — always ask for the price before you buy
- Add 15–20% waste for furniture or cabinet projects where you have many pieces to cut
- Nominal vs actual: a "2×4" is actually 1.5" × 3.5" — use actual dimensions for precise calculations
Recommended Products
Frequently Asked Questions
What is a board foot?
A board foot is a unit of lumber volume equal to 144 cubic inches — the equivalent of a board 1 inch thick, 12 inches wide, and 12 inches long. It is the standard unit for pricing hardwood lumber.
How many board feet are in a 2×4×8?
Using nominal dimensions: (2 × 4 × 8) / 12 = 5.33 board feet. Using actual dimensions (1.5" × 3.5" × 8'): (1.5 × 3.5 × 8) / 12 = 3.5 board feet.
Is dimensional lumber sold in board feet?
Dimensional framing lumber (2×4, 2×6, etc.) is typically sold by linear foot at home improvement stores. Board feet pricing is most common at hardwood dealers and sawmills.
What is a fair price per board foot for hardwood?
Common hardwoods like oak and ash run $5–$10/BF. Premium hardwoods like walnut or cherry can be $12–$20/BF. Exotic species may exceed $30/BF. Prices vary significantly by region and supplier.
How do I calculate board feet for a project with many different pieces?
Calculate each piece size separately, then add the totals. Most woodworkers add 15–20% to their total for waste from cuts and defects. Use a cutting diagram to minimize waste.