Board Foot Calculator

How to use the Board Foot Calculator

1. 1Enter the thickness, the width, the length, the number of pieces and an optional price.
2. 2Pick the units or options from the menus if the board feet tool offers them.
3. 3Read the board feet in the large result box.
4. 4Look at the extra rows for related figures.
5. 5Press Copy result to keep the answer.

When you need the board feet

Woodworkers use board feet to compare prices between boards of different sizes, and to make sure they buy enough for a project. Sawmills and lumber yards sell hardwood by the board foot, so the figure is how you read the price tag.

Plan your project in board feet, then add 15 to 20 percent for waste, grain matching and defects. Note that thickness is the nominal rough thickness, such as 4/4 for one inch.

How the board feet is worked out

Board feet = thickness (in) × width (in) × length (ft) ÷ 12, multiplied by the number of pieces. A board 2 inches thick, 6 inches wide and 8 feet long is 2 × 6 × 8 ÷ 12 = 8 board feet. Ten of them are 80 board feet, which at 4.50 per board foot costs 360. In metric terms, 80 board feet is about 0.189 cubic metres.

Every answer on this page comes from that one rule, so you can check any result by hand with a calculator. The figures shown underneath, such as other units, are conversions of the same answer.

• Pieces and price
• Result in cubic metres too
• Cost shown

Mistakes to avoid with board feet

Using the nominal size, such as a 2×4 of 1.5 by 3.5 inches, gives a different result from the actual size. Lumber yards generally price on the nominal or rough size, so ask which they use. Also, remember that lengths are in feet but thickness and width in inches.

On phone and computer

On a phone, type into the boxes one after another and read the board feet underneath; Copy result puts it on the clipboard for a message or a note. On a computer the inputs sit on the left and the answer on the right, so you can change one figure and watch the board feet move. The board foot calculator works the same on both. Lumber jobs usually involve other volumes and surfaces. Use Volume Calculator for boxes and cylinders, Area Calculator for floors and walls, Tile Calculator and Concrete Calculator for the work that surrounds the timber.

Features

• Add 15 to 20 percent for waste
• Thickness and width in inches
• Ask if the price uses nominal sizes
• Clear messages when the board feet inputs make no sense
• Copy the result with one tap
• Private: nothing is uploaded

Frequently asked questions