What is a board foot?
A board foot is (thickness in inches x width in inches x length in feet) / 12 -- the standard nominal-dimension board-foot formula used across the lumber trade.
Board Foot and Lumber Quantity Calculator
Board footage and piece count for a lumber list, from nominal dimensions.
This lumber order totals — board feet.
Lumber pieces
Board footage uses nominal (as-sold) dimensions. Length accepts a plain number in feet, or tape-measure notation like 10' 6-3/4".
This lumber order totals — board feet.
You'll need
Board foot and lumber quantity
Warnings
- ERROR Add at least one lumber piece.
Detail values
Assumptions
- Dimensions: Nominal (as-sold) dimensions, not dressed/actual size
Included: lumber pieces as entered.
Not included: labor, delivery, permits, disposal of waste material.
Formula details
- Board feet per piece: (thicknessIn x widthIn x lengthFt) / 12
Arithmetic identity, not an estimating rule: a board foot IS 144 cubic inches (1 in x 12 in x 12 in), so (T x W x L_in)/144 and (T x W x L_ft)/12 are the same division. Nothing external supports it and nothing needs to. Measured on nominal, as-sold dimensions -- see the assumption below.
- Board feet total: sum(boardFeetEach x quantity)
Material List
About this calculator
Add each lumber piece type you need with its nominal dimensions and quantity.
FAQ
Does this use actual or nominal dimensions?
Nominal (as-sold) dimensions -- a 2x4 is entered as 2 in x 4 in, not its dressed actual size of 1.5 in x 3.5 in, matching how lumber is bought and sold.