Board Foot Calculator
Estimate the volume (and cost) of hardwood lumber in board feet.
This board foot calculator quickly estimates the volume of hardwood lumber you plan to buy and how much it will cost. A board foot measures volume, not area — it's the standard way to price rough lumber in the US and Canada.
How the Math Works
The board foot calculator uses a straightforward formula to measure lumber volume: board feet = length (ft) × width (in) × thickness (in) ÷ 12. This equation converts the dimensions of hardwood planks into board feet, a standard unit in the lumber industry. The division by 12 adjusts for unit inconsistencies, as length is in feet while width and thickness are in inches. Multiplying these three measurements gives the total cubic inches, and dividing by 144 (12×12) converts it to board feet, ensuring accurate and consistent results for professionals and DIY enthusiasts alike.
Practical Applications
To apply this calculation practically, measure the length of your lumber in feet and the width and thickness in inches. For example, a board that is 8 feet long, 10 inches wide, and 1 inch thick would equal 8 × 10 × 1 ÷ 12 = 6.67 board feet. This helps in estimating material needs for projects like furniture, flooring, or construction. You can also reverse-calculate required dimensions to achieve a specific board foot quantity, ensuring you purchase the right amount without overbuying or shortages.
Day-to-Day Use
In everyday life, this calculator simplifies budgeting for woodworking or home improvement projects. By determining the board feet needed, you can quickly estimate costs based on local lumber prices (often quoted per board foot) and compare options across different timber types or suppliers. Whether you're a hobbyist crafting a bookshelf or a contractor ordering materials, knowing the exact volume helps avoid waste, prevents unexpected expenses, and streamlines decision-making for both small DIY tasks and large-scale builds.
Worked example
Five hardwood boards, each 8 ft long, 10 in wide and 1.25 in thick: per board = 8 × 10 × 1.25 ÷ 12 = 8.33 BF total = 5 × 8.33 = 41.67 BF At $4.15 / BF → cost = 41.67 × 4.15 = $172.92.
FAQ
How many board feet are in a 2x4?
A 2x4 is 2 in × 4 in. For an 8 ft length: 8 × 4 × 2 ÷ 12 = 5.33 BF. For 12 ft it's 8 BF, for 16 ft it's 10.67 BF.
Board foot vs linear foot — what's the difference?
A board foot is a measure of volume (width × length × thickness). A linear foot is simply 12 inches of length, ignoring width and thickness.
How much does a board foot of oak weigh?
About 3.08–4.67 lb (1.42–2.12 kg), averaging ~3.875 lb, because oak density ranges 37–56 lb/ft³.