Lumber Calculator
Calculate rough lumber needs for framing and general carpentry projects.
Step 1: Units
Step 2
Enter project measurements
Use decimals if needed (e.g. 3.5).
How to use this calculator
Enter project dimensions and board assumptions to estimate lumber quantity.
What the math is doing
BF = (t × w × L) ÷ 12 with inches and feet as described.
Frequently asked questions
Nominal vs actual?
A 2×4 is not 2 in by 4 in; measure if precision matters.
Hardwood vs softwood?
BF math is the same; pricing differs.
Linear feet mode?
Use the deck board calculator instead.
Moisture content?
Green lumber shrinks; buy for final use conditions.