Free estimate — verify against local code before building
Lumber Calculator
Plan a repeated lumber size with board, volume, weight, and cost totals.
What this calculator includes
Convert one repeated lumber size into board count with waste, total board feet, linear feet, physical volume, optional planning weight, and cost. Price by the board or board foot and keep density assumptions visible.
How to use this lumber calculator
- 01
Enter one board size
Use the dimensions on which your supplier prices the stock. Nominal construction sizes and actual dressed dimensions are not interchangeable for physical volume.
- 02
Count required pieces
Enter the cut-list quantity before waste, then set an allowance for defects, selection, and offcuts. The calculator rounds up to whole boards.
- 03
Choose a price basis
Use price per board for dimensional lumber or price per board foot for rough hardwood. Leave price blank when you only need quantity.
- 04
Use weight carefully
Choose a species or custom density for a planning weight. Actual weight changes with species, moisture, treatment, and individual boards.
Worked example
Example: twenty 2 × 6 × 10 ft boards
Each board is 10 board feet by nominal dimensions. A 10% allowance raises 20 required boards to 22 boards, for 220 board feet and 220 linear feet. At a price per board, cost is 22 times the entered price.
Practical buying and overage guidance
Build a cut list before setting waste, then confirm grade, species, treatment, moisture, straightness, usable length, nominal versus actual size, stock availability, and delivery limits. Keep long clear pieces separate from short blocking stock.
Calculation sources and review
Primary references and formula assumptions are linked so you can verify them against the selected product, supplier, and adopted local requirements.
Internal formula review completed July 13, 2026. What this review covers
- USDA Forest Products Laboratory — Wood Handbook (opens in a new tab)
Wood properties, density variation, moisture, nominal dimensions, and engineering context.
- National Hardwood Lumber Association (opens in a new tab)
Hardwood board-foot tally conventions.
- American Wood Council — design tools and standards (opens in a new tab)
Structural use requires species-, grade-, load-, span-, and connection-specific design.
Frequently asked questions
How are board feet calculated?
Board feet per board equal thickness in inches × width in inches × length in feet ÷ 12. Multiply by the board count for the total.
What is the difference between board feet and linear feet?
Board feet measure volume; linear feet measure length only. Two boards with the same length but different thickness or width have equal linear feet and different board feet.
Should I enter nominal or actual dimensions?
Use the basis required for the result. Hardwood sold by board foot usually uses nominal rough dimensions. For physical volume and weight of dressed stock, actual measured dimensions are more representative.
How does the waste allowance work?
It increases the requested piece count and rounds up to a whole board. This reflects how lumber is purchased and makes board-foot, linear-foot, volume, weight, and cost totals agree with the order count.
How accurate is the lumber weight estimate?
It is a handling estimate only. Wood density varies with species, growth, grade, moisture, treatment, and storage; use supplier weights for transport and lifting decisions.