How to Calculate Board Feet: A Simple Guide for Woodworkers



When working with lumber, it’s crucial to know how to calculate board feet accurately. A board foot is a unit of measurement used for lumber, representing a volume of 12 inches x 12 inches x 1 inch. Here’s how you can calculate it.

The Board Foot Formula

The formula for calculating board feet is:

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

For example, a 2” x 4” x 10’ board would be calculated as:

2 x 4 x 10 ÷ 12 = 6.667 Board Feet

Here’s a second method to calculate board feet using only inches:

(Thickness in inches) x (Width in inches) x (Length in inches) ÷ 144 = Board Feet

For example, if you have a board that is 2 inches thick, 6 inches wide, and 120 inches long:

2 x 6 x 120 ÷ 144 = 10 Board Feet

This method is useful when all dimensions of your lumber are in inches, such as when working with smaller pieces of wood or when precision is needed.

Step-by-Step Calculation

1. Measure: Record the thickness, width, and length of your lumber.
2. Multiply: Multiply the three dimensions together.
3. Divide: To get the board feet, divide the total by 12 or 144 depending on your method.

Common Lumber Sizes

• 1x4 board: 0.334 board feet per foot
• 2x4 board: 0.667 board feet per foot
• 2x6 board: 1 board foot per foot

By mastering board foot calculations, you’ll better estimate costs and materials for any woodworking project.

Optimizing Your Lumber Purchase

Knowing how to calculate board feet can also help you make informed decisions when purchasing lumber. You can avoid waste and ensure that you have enough material for your project.

Conclusion

Understanding how to calculate board feet is essential for woodworkers, carpenters, and anyone involved in construction. Accurate measurements save time, money, and resources, making your projects more efficient.

For more detailed information, visit Wood-Mizer’s Guide to Board Feet.