Measure boards with confidence
Lumber Board Foot Calculator
Plan a complete lumber order with multiple board sizes, waste allowances, clear pricing, and weight from actual dimensions.
How to calculate board feet and lumber cost
Add one row for every board size and stock length. Enter the number of boards needed before waste. Use the purchasing thickness and width specified by your supplier, and choose a price per board or per board foot. Actual thickness and width determine the physical volume and weight estimate.
Order quantity = round up (required boards × (1 + waste ÷ 100))
Weight (lb) = actual volume (cubic feet) × density (lb per cubic foot)
For metric inputs, the calculator converts millimeters to inches and meters to feet before calculating board feet. One board foot equals 144 cubic inches, or 1/12 cubic foot.
Example: ordering ten 2 × 4 boards
Ten 8-foot boards with a 10% allowance require 11 boards. Using purchasing dimensions of 2 × 4 inches gives 5.33 board feet per board and 58.67 board feet in the order. At 6 per board, the subtotal is 66; with 8% tax, the total is 71.28.
With actual dimensions of 1.5 × 3.5 inches and an assumed density of 35 lb per cubic foot, those 11 boards weigh approximately 112.3 lb. These dimensions and density are illustrative inputs, not a specification for every product.
Lumber calculator questions
Should I use nominal or actual dimensions?
Use your supplier's tally dimensions for purchasing board feet. Use measured finished dimensions for actual volume and weight. A nominal label is not a measurement of the finished board.
How accurate is the weight estimate?
Weight depends on species, moisture, treatment, and actual dimensions. Enter a density appropriate to your stock. The default 35 lb per cubic foot is an editable planning assumption; it is not a certified load rating.
Does the allowance optimize cuts?
No. It adds whole stock boards to each size. It does not arrange cuts, account for saw kerf, or assess structural suitability.
Is my list saved?
The latest valid list is saved in this browser when local storage is available. Export CSV for a portable copy, or print the itemized order.
