A powerful and user-friendly calculator to determine board feet for lumber.
Board Foot Calculator
Use this tool to calculate the total board feet for your woodworking project. Just enter the dimensions of your lumber and the number of pieces.
Your total board feet will be displayed here.
How Is Board Foot Calculated?
The formula for calculating board feet is:
(Thickness in inches × Width in inches × Length in feet) ÷ 12
The division by 12 is because a single board foot is equivalent to a piece of wood measuring 1 inch thick, 12 inches wide, and 1 foot long.
10 Practical Board Foot Examples
Learn how to calculate board feet for different projects.
Example 1: Building a Table
Dimensions: 1.5" thick, 10" wide, 6' long. Number of Pieces: 4.
Calculation: (1.5 × 10 × 6) ÷ 12 = 7.5 board feet per piece. Total: 7.5 × 4 = 30 board feet.
Example 2: Making a Bed Frame
Dimensions: 2" thick, 8" wide, 8' long. Number of Pieces: 6.
Calculation: (2 × 8 × 8) ÷ 12 = 10.67 board feet per piece. Total: 10.67 × 6 = 64.02 board feet.
Example 3: Installing Wood Flooring
Dimensions: 0.75" thick, 5" wide, 4' long. Number of Pieces: 250.
Calculation: (0.75 × 5 × 4) ÷ 12 = 1.25 board feet per piece. Total: 1.25 × 250 = 312.5 board feet.
Example 4: Storage Shelves
Dimensions: 1" thick, 12" wide, 3' long. Number of Pieces: 8.
Calculation: (1 × 12 × 3) ÷ 12 = 3 board feet per piece. Total: 3 × 8 = 24 board feet.
Example 5: Window Trim
Dimensions: 0.5" thick, 4" wide, 5' long. Number of Pieces: 10.
Calculation: (0.5 × 4 × 5) ÷ 12 = 0.83 board feet per piece. Total: 0.83 × 10 = 8.3 board feet.
Example 6: Building a Fence
Dimensions: 1" thick, 6" wide, 6' long. Number of Pieces: 50.
Calculation: (1 × 6 × 6) ÷ 12 = 3 board feet per piece. Total: 3 × 50 = 150 board feet.
Example 7: Kitchen Cabinetry
Dimensions: 0.75" thick, 12" wide, 8' long. Number of Pieces: 15.
Calculation: (0.75 × 12 × 8) ÷ 12 = 6 board feet per piece. Total: 6 × 15 = 90 board feet.
Example 8: Small Project (Box)
Dimensions: 0.5" thick, 8" wide, 2' long. Number of Pieces: 4.
Calculation: (0.5 × 8 × 2) ÷ 12 = 0.67 board feet per piece. Total: 0.67 × 4 = 2.68 board feet.
Example 9: Ceiling Joists
Dimensions: 2" thick, 10" wide, 16' long. Number of Pieces: 20.
Calculation: (2 × 10 × 16) ÷ 12 = 26.67 board feet per piece. Total: 26.67 × 20 = 533.4 board feet.
Example 10: Wood Siding
Dimensions: 1" thick, 4" wide, 10' long. Number of Pieces: 30.
Calculation: (1 × 4 × 10) ÷ 12 = 3.33 board feet per piece. Total: 3.33 × 30 = 99.9 board feet.
Frequently Asked Questions
1. What is a board foot?
A board foot is a unit of volume for timber in North America, used to determine the price of rough lumber. One board foot is equivalent to a piece of wood measuring 1 inch thick, 12 inches wide, and 1 foot long.
2. Can I use different units (e.g., centimeters or meters)?
This calculator is designed to use inches for thickness and width, and feet for length. If your measurements are in other units, you must convert them first. (1 inch = 2.54 cm, 1 foot = 30.48 cm).
3. Does the type of wood affect the calculation?
No, the calculation only depends on the geometric dimensions of the wood (thickness, width, length). However, the price per board foot will vary depending on the type of wood.
4. How do I calculate the total cost of the lumber?
After getting the total board feet, you can multiply it by the price per board foot quoted by your supplier. Total Cost = (Total Board Feet) × (Price per Board Foot).
5. What are the minimum and maximum values I can enter?
All dimensions and the number of pieces must be positive numbers. The calculator is intended for use with reasonable dimensions for standard woodworking projects.