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Board Feet Calculator — Lumber Volume & Cost Estimator

Board Feet = (Thickness" × Width" × Length') ÷ 12

Example: A standard 2×6 board that is 10 feet long = (2 × 6 × 10) ÷ 12 = 10 board feet.

Board feet (BF) is the universal lumber volume unit used by sawmills, lumber yards, and woodworkers across North America. Unlike linear feet which only measures length, board feet accounts for the full 3-dimensional volume — thickness, width, and length — making it the standard for pricing hardwoods, softwoods, and structural timbers. Use this calculator to estimate material volume and total cost for any project.

Lumber Dimensions

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Calculated Results

Board Feet per Board 10.00 BF
Total Board Feet (all boards) 10.00 BF
Estimated Material Cost $25.00
Equivalent Cubic Feet 0.833 ft³

Board Feet Reference Chart — Common Lumber Sizes

This chart shows pre-calculated board feet for the most common nominal lumber sizes at standard lengths. Note that nominal dimensions (2×4, 2×6) are slightly larger than actual dressed dimensions, but board feet is always calculated using the nominal size.

Nominal Size 6 ft 8 ft 10 ft 12 ft
1×4 2.00 BF2.67 BF3.33 BF4.00 BF
1×6 3.00 BF4.00 BF5.00 BF6.00 BF
2×4 4.00 BF5.33 BF6.67 BF8.00 BF
2×6 6.00 BF8.00 BF10.00 BF12.00 BF
2×8 8.00 BF10.67 BF13.33 BF16.00 BF
2×10 10.00 BF13.33 BF16.67 BF20.00 BF

Why Board Feet Matter in Woodworking

Hardwood lumber — oak, maple, walnut, cherry — is sold exclusively by the board foot because each plank varies in width, thickness, and length. When buying rough-sawn lumber from a sawmill or specialty lumber dealer, you pay a per-board-foot price. Calculating exact board feet prevents over-ordering expensive hardwoods and ensures accurate project material budgets.

Softwood dimensional lumber (2×4, 2×6, etc.) sold at home improvement stores is typically priced by the linear foot, but large commercial orders from building supply wholesalers revert to board feet pricing. Contractors ordering structural framing lumber in bulk always use board feet for quotes and invoices.

Board Foot vs. Linear Foot vs. Running Foot

A linear foot (or running foot) only measures length — it ignores thickness and width. One linear foot of a 2×4 and one linear foot of a 2×10 are the same in linear measure, but vastly different in material volume. For any project where material volume matters (pricing, structural loads, weight calculations), always use board feet.

The board foot formula standardizes all lumber to a common volume unit, making it easy to compare prices between different sizes and species at different suppliers.

Frequently Asked Questions — Board Feet

What is a board foot?
A board foot (BF) is a specialized unit of lumber volume used in the US and Canada. It equals a piece of wood that is 12 inches wide, 12 inches long, and 1 inch thick — equivalent to 144 cubic inches or 1/12 of a cubic foot. Lumber prices at sawmills are quoted per board foot.
How do you calculate board feet?
Board Feet = (Thickness in inches × Width in inches × Length in feet) ÷ 12. Example: A 2×4 board that is 8 feet long = (2 × 4 × 8) ÷ 12 = 5.33 board feet. For length in inches instead of feet, divide by 144 instead.
How many board feet are in a 2x4x8?
A standard 2×4 that is 8 feet long contains (2 × 4 × 8) ÷ 12 = 5.33 board feet. A 2×4×10 contains 6.67 BF, and a 2×4×12 contains 8 BF.
How many board feet are in a 2x6x8?
A 2×6 that is 8 feet long contains (2 × 6 × 8) ÷ 12 = 8 board feet. A 2×6×10 = 10 BF, a 2×6×12 = 12 BF.
How do you convert board feet to cubic feet?
Divide board feet by 12 to get cubic feet. For example, 120 board feet = 10 cubic feet. This is because 1 board foot = 1/12 cubic foot.
Why is lumber measured in board feet instead of linear feet?
Linear feet only measures length, not volume. Board feet accounts for all three dimensions (thickness × width × length), giving a standardized volume measure for pricing lumber regardless of its cross-section profile.

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