Board Foot Calculator
Convert lumber dimensions (thickness, width, length) into board feet. Calculate volume in board feet and cubic feet.
Formula & Explanation
The board foot calculator converts lumber dimensions into volume measurements. **Board Feet** = (thickness (in) × width (in) × length (ft)) ÷ 12 Alternatively: **Board Feet** = (thickness × width × length (in)) ÷ 144 **Cubic Feet** = (thickness (in) × width (in) × length (in)) ÷ 1,728 A board foot is a standard unit of lumber volume in the construction industry: 1 bf = 1 inch thick × 12 inches wide × 12 inches long (144 cubic inches). All lumber is priced by the board foot. For example, a 2×4×8 board measures 2 inches × 4 inches × 8 feet, which equals (2 × 4 × 8) ÷ 12 = 5.33 board feet.
Assumptions
- •Dimensions are assumed to be in nominal size (e.g., a "2×4" is actually 1.5" × 3.5" after kiln drying and planing)
- •Board foot calculations use nominal dimensions, per industry standard (not actual dimensions)
- •Length is entered in feet; multiply by 12 to convert to inches for the formula
- •This calculator does not account for waste, cutting loss, or lumber grade
- •Prices and availability vary by lumber type, grade, region, and market conditions
Example Calculation
A common 2×4×8 board (nominal dimensions) measures 5.33 board feet and 0.44 cubic feet. This is a classic example used in construction and lumber pricing.
Inputs
Results
Common Lumber Board Feet
| size | boardFeet | cubicFeet |
|---|---|---|
| 1×4×8 | 2.67 | 0.22 |
| 1×6×8 | 4 | 0.33 |
| 1×8×8 | 5.33 | 0.44 |
| 1×10×8 | 6.67 | 0.56 |
| 1×12×8 | 8 | 0.67 |
| 2×4×8 | 5.33 | 0.44 |
| 2×6×8 | 8 | 0.67 |
| 2×8×8 | 10.67 | 0.89 |
| 2×10×8 | 13.33 | 1.11 |
| 2×12×8 | 16 | 1.33 |
| 2×4×12 | 8 | 0.67 |
| 2×4×16 | 10.67 | 0.89 |
| 2×6×12 | 12 | 1 |
| 2×6×16 | 16 | 1.33 |
| 4×4×8 | 10.67 | 0.89 |
Frequently Asked Questions
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