Board Foot Calculator

The Unit That Actually Matches How Lumber Is Priced

Hardwood lumber isn't priced by the linear foot the way construction lumber often is — it's priced by the board foot, a volume measurement equal to a piece of wood 1 inch thick, 12 inches wide, and 1 foot long. Any other dimensions convert to an equivalent board-foot volume, which is the number that actually matters when comparing prices or ordering from a hardwood supplier.

The Formula

Board Feet (per board) = (Thickness(in) × Width(in) × Length(ft)) ÷ 12
Total Board Feet = Board Feet per Board × Quantity

Worked Example

10 boards, each 1 in thick, 6 in wide, 8 ft long
MetricValue
Board feet per board4.0 bd ft
Quantity10 boards
Total board feet40.0 bd ft

Because board feet is a volume measure, a thicker board of the same width and length contains proportionally more board feet — doubling thickness from 1″ to 2″ doubles the board-foot count for the same length and width.

Where This Matters

  • Getting an accurate quote from a hardwood dealer — most hardwood suppliers price per board foot, so converting your project's dimensions to board feet is necessary before you can compare their quote against your budget.
  • Ordering the right quantity — miscalculating board feet on a large order either leaves you short mid-project or with an expensive surplus of hardwood.
  • Comparing rough-sawn versus surfaced lumber pricing — rough lumber is typically sold and measured by its nominal (pre-planing) thickness, so board-foot calculations should use the nominal dimension, not the final surfaced thickness.

How to Use This Calculator

  1. Enter the Thickness in inches.
  2. Enter the Width in inches.
  3. Enter the Length in feet.
  4. Enter the Quantity of Boards.
  5. Select Calculate to see board feet per board and the total.

Related Calculations

Turn board feet into a dollar cost with the Lumber Cost Calculator, or work out how many pieces a board yields with the Wood Cutting Calculator.