How Do I Figure Out How Many Board Feet I Need?

If you’re buying lumber for a woodworking project, flooring, shelving, furniture, or construction, knowing how many board feet you need can help you estimate the amount of wood to purchase and avoid buying too much or too little.

A board foot is a measurement of lumber volume equal to a board that is 1 foot long, 1 foot wide, and 1 inch thick.

Board Foot Formula

To calculate board feet, use:

Board Feet = (Thickness in inches × Width in inches × Length in feet) ÷ 12

For example, if you have a board that is:

  • 2 inches thick
  • 8 inches wide
  • 10 feet long

The calculation is:

(2 × 8 × 10) ÷ 12 = 13.33 board feet

So, one board contains approximately 13.33 board feet.

How Many Board Feet Do I Need?

If your project requires several pieces of lumber, calculate the board feet for each piece and add them together.

For example:

  • 4 boards × 13.33 board feet = 53.32 board feet

It’s also a good idea to account for cutting waste, defects, and mistakes. Depending on your project, adding 10–20% extra lumber can provide a reasonable allowance.

Use a Board Foot Calculator

For a faster estimate, you can enter the lumber thickness, width, length, and quantity into a board foot calculator. This is especially useful when you’re working with multiple boards or different lumber dimensions.

Knowing your total board feet before purchasing lumber makes it easier to estimate material requirements and compare lumber prices.

Scroll to Top