Concrete and materials

Board foot calculator: how to figure board feet

Hardwood and a lot of rough lumber are sold by the board foot, a unit of volume. Here is the formula, how yards apply it, and a few examples to check a quote.

What is a board foot?

One board foot is a piece 1 in thick, 12 in wide and 12 in long: 144 cubic inches of wood.

How do you calculate board feet?

Board feet = thickness (in) × width (in) × length (ft) ÷ 12. Multiply by the number of pieces on your cut list for the total.

Example. Ten 2x6 boards 12 ft long: 2 × 6 × 12 ÷ 12 = 12 board feet each, 120 board feet in all.

Hardwood thickness in quarters

Rough hardwood is sold by its thickness in quarter inches: 4/4 is 1 in, 6/4 is 1 1/2 in, 8/4 is 2 in.

Example. One 8/4 board, 7 in wide and 10 ft long: 2 × 7 × 10 ÷ 12 = 11.67 board feet.

Nominal or actual size?

A 2x6 measures 1 1/2 in by 5 1/2 in once it is dried and planed, but many yards count it as 2 by 6 when they price by the board foot. Hardwood is usually measured rough, before planing. Ask your supplier which sizes it uses and type those.

Linear feet versus board feet

A linear foot is just a foot of length, whatever the size; deck boards and trim are often priced this way. A 1x6 is 0.5 board feet per linear foot, a 2x12 is 2 board feet per linear foot.

Board feet in Clad

Clad's board feet tool takes the thickness, width, length and number of pieces, gives the board feet each and in all, and with a price per board foot the cost, which goes into the job's shopping list.