Understanding the Lumber Calculator
A lumber calculator helps you determine board feet, the number of boards, or the cost of lumber for a project. Whether framing, building furniture, or fencing, it turns your cut list into the quantity and cost of wood to buy.
What a board foot is
Lumber is often priced by the board foot — a volume measure equal to a piece 1 inch thick, 12 inches wide, and 12 inches long. The calculator converts your dimensions into board feet, which is how lumberyards quote hardwood and rough lumber, so you can compare prices and budget accurately.
Nominal vs. actual size
A “2x4” is not actually 2 by 4 inches — after milling and drying it measures about 1.5 by 3.5 inches. This nominal-versus-actual difference matters when planning tight-fitting builds. Always add some extra for cutting waste, defects, and mistakes, especially on a first-time project.
Tips & things to know
- •A “2x4” actually measures about 1.5 x 3.5 inches.
- •Hardwood is often priced by the board foot.
- •Buy extra for waste, defects, and cutting mistakes.