Construction tools
Board Foot Calculator
Calculate lumber board feet, a visible allowance, and optional material-only cost.
Board foot estimate
Enter the dimensions used for the lumber tally. Nominal and actual dimensions are not interchangeable.
The lumber board-foot formula
For each board, the calculator uses (thickness in × width in × length ft) ÷ 12, multiplies by whole-board quantity, and then applies the visible allowance.
A board foot is a lumber volume of 12 inches by 12 inches by 1 inch. This calculator is for board dimensions, not log scaling.
Method & sources
Optional cost multiplies order board feet by the entered price without adding tax, delivery, or supplier minimums.
Important limits
- Enter the dimensions used by your seller; nominal and surfaced actual dimensions are not interchangeable.
- This does not grade lumber, optimize a cut list, predict yield, or convert log scale to finished lumber.
- Confirm tally conventions, species, grade, moisture condition, price, and availability with the supplier.
Reviewed references
- U.S. Forest Service: Rough Mill Improvement Guide for Managers and Supervisors
Reviewed 2026-07-21. Defines one board foot and gives the thickness-by-width-by-length lumber formula used by this calculator.
- Inch Calculator: Board Foot Calculator
Reviewed 2026-07-21. Competitive research only: informed dimension, quantity, and price input flow.