Lumber calculator

Convert pieces to board feet and linear feet and price a lumber order.

lbt
Letters on the drawing match the letters next to the inputs.
in
in
ft
pcs
More settings
$
Volume5.8 ft³

Shopping list

  • Pieces20 pcs
  • Volume5.8 ft³
  • Linear feet160 ft
  • Board feet107 board ft

How we got there

Volume of one piece
0.29 ft³

Results are estimates. Always check the coverage printed on the product and your local building code.

How it is calculated

Dimensional lumber is named by nominal size: a 2×4 is actually 1.5 × 3.5 in. Board feet use the nominal size: thickness × width (in) × length (ft) ÷ 12. Linear feet are pieces × length. Cost uses the price per piece, per linear foot or per board foot, as your yard lists it.

FormulaBoard feet = nominal thickness × nominal width × length (ft) ÷ 12Linear feet = pieces × lengthVolume uses the actual size

Example

Twenty 2×4s 8 ft long are 160 linear feet and 107 board feet; each 2×4×8 is 5.33 board feet.

Tips from practice

  • Add 10 % for crooked boards, knots and cutoffs.
  • Pressure-treated lumber is wetter and heavier; let it dry before staining.
  • Studs for 8 ft walls are precut to 92 5/8 in.

Questions and answers

How many board feet is a 2×4×8?

5.33 board feet: 2 × 4 × 8 ÷ 12.

How many board feet is a 2×6×10?

10 board feet: 2 × 6 × 10 ÷ 12.

What are the actual sizes of lumber?

2×4 is 1.5 × 3.5 in, 2×6 is 1.5 × 5.5 in, 2×8 is 1.5 × 7.25 in, 4×4 is 3.5 × 3.5 in.

Found a mistake in a formula? Write to [email protected]