Board foot calculator

Calculate board feet for lumber purchasing. One board foot = 144 cubic inches (1" x 12" x 12").

in
Nominal (rough)
in
in
8.0 ft
$/BF
Board
96" (8.0 ft)6"1"
Board feet (each)
4.00
BF
Total (x1)
4.00
BF
Estimated cost
$20.00
@ $5/BF
Volume (each)
0.333 cu ft
576 cu in

What Is a Board Foot?

A board foot is the standard unit for measuring and pricing rough lumber. One board foot equals 144 cubic inches — equivalent to a board 1 inch thick, 12 inches wide, and 12 inches long.

The formula is simple: Board Feet = (Thickness x Width x Length) / 144where all dimensions are in inches. For rough lumber, use nominal dimensions. For surfaced lumber (S4S), use actual dimensions for a more accurate volume but nominal for pricing since that's how mills sell it.

Common Board Foot Values

  • 1x6x8' = 4 board feet
  • 1x12x8' = 8 board feet
  • 2x6x8' = 8 board feet
  • 2x12x12' = 24 board feet
  • 4/4 (1") hardwood: 1 BF per square foot of surface
  • 8/4 (2") hardwood: 2 BF per square foot of surface
These calculators are provided for estimation and educational purposes only.