Board Foot Formula
Board feet = (Thickness in inches × Width in inches × Length in feet) ÷ 12. A single 2×6 at 8 ft = (1.5 × 5.5 × 8) ÷ 12 = 5.5 BF. Multiply by quantity for total project volume.
Linear feet measures length only—use it for trim and decking. Use board feet for hardwood and specialty lumber priced by volume.
Frequently Asked Questions
Why are lumber dimensions different from the name?
Nominal sizes (2×4) refer to the rough-sawn dimension before drying and planing. The finished (actual) size is smaller — a 2×4 is really 1.5×3.5 inches.
What is a board foot?
One board foot equals a piece 1 inch thick × 12 inches wide × 12 inches long (144 cubic inches). It is the standard unit for pricing hardwood and specialty lumber.