Volume Lumber Calculator | Board Feet and Cubic Volume
Calculate lumber volume in board feet, cubic feet, and cubic meters. Enter dimensions or quick-select common lumber sizes like 2x4, 2x6, or 4x4. Includes cost estimation based on price per board foot. See also our board foot calculator and concrete calculator for construction projects.
How to Calculate Lumber Volume
- Enter the actual thickness of the lumber in inches (e.g., 1.5 for a 2x4).
- Enter the actual width in inches (e.g., 3.5 for a 2x4).
- Enter the length in feet.
- Enter the quantity of pieces.
- Optionally enter price per board foot for cost estimation.
- Click Calculate to see board feet, cubic feet, and cubic meters.
Formula
Board Feet = (Thickness" × Width" × Length' × 12) / 144 × Quantity
Cubic Feet = (Thickness" × Width" × Length" ) / 1728 × Quantity
Cubic Meters = Cubic Feet × 0.0283168
Cost = Board Feet × Price per Board Foot
Note: 1 board foot = 144 cubic inches = 1" × 12" × 12"Example
Calculate volume of 10 pieces of 2x4 lumber, 8 feet long:
Actual dimensions: 1.5" × 3.5" × 8'
Board Feet = (1.5 × 3.5 × 8 × 12) / 144 × 10 = 35.0 BF
Cubic Feet = (1.5 × 3.5 × 96) / 1728 × 10 = 2.917 ft³
Cubic Meters = 2.917 × 0.0283168 = 0.0826 m³
At $5.50/BF: Cost = 35.0 × $5.50 = $192.50
Common Lumber Sizes Reference Table
| Nominal | Actual (in) | BF per 8' | BF per 12' |
|---|---|---|---|
| 2x4 | 1.5 × 3.5 | 3.50 | 5.25 |
| 2x6 | 1.5 × 5.5 | 5.50 | 8.25 |
| 2x8 | 1.5 × 7.25 | 7.25 | 10.88 |
| 2x10 | 1.5 × 9.25 | 9.25 | 13.88 |
| 2x12 | 1.5 × 11.25 | 11.25 | 16.88 |
| 4x4 | 3.5 × 3.5 | 8.17 | 12.25 |
| 6x6 | 5.5 × 5.5 | 20.17 | 30.25 |
Frequently Asked Questions
What is a board foot?
A board foot (BF) is a unit of lumber volume equal to 144 cubic inches, or a piece 1 inch thick, 12 inches wide, and 12 inches long. It is the standard unit for pricing hardwood lumber in North America.
Why are actual lumber dimensions smaller than nominal?
Nominal dimensions (like 2x4) refer to the rough-sawn size before drying and planing. After kiln drying and surfacing, a 2x4 becomes 1.5 x 3.5 inches. Always use actual dimensions for volume calculations.
How do I convert board feet to cubic meters?
1 board foot = 1/12 cubic foot = 0.002360 cubic meters. Multiply board feet by 0.002360 to get cubic meters, or convert to cubic feet first (BF/12) then multiply by 0.0283168.
Should I use nominal or actual dimensions?
For accurate volume calculations, always use actual dimensions. For ordering lumber by the board foot at a lumberyard, some suppliers use nominal dimensions in their pricing. This calculator uses actual dimensions for precision.
How much does lumber weigh per board foot?
Weight varies by species and moisture content. Kiln-dried softwood (pine, spruce) weighs about 2.5-3.5 lbs per board foot. Hardwoods like oak weigh 4-5 lbs per board foot. Green (wet) lumber can weigh 50-100% more.