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Board Feet
—BF
Enter dimensions above
With 10% Waste (BF)
—BF
Based on Lumber density (0.5 t/yd³)
Free Lumber Calculator
Lumber Calculator: Board Feet Without the Headache
Enter your board dimensions and quantity into the lumber calculator above to instantly get total board feet, plus 2026 price estimates for your project.
Common Boards: Board Feet Reference
| 2×4 × 8 ft | 5.33 board feet |
| 2×4 × 10 ft | 6.67 board feet |
| 2×6 × 12 ft | 12 board feet |
| 4×4 × 8 ft (post) | 10.67 board feet |
Lumber Reference Guide
Lumber Prices in 2026 (per Board Foot)
| Pine / fir framing lumber | $1.50 – $3.00 |
| Pressure-treated pine | $2.00 – $4.00 |
| Cedar / redwood | $3.00 – $8.00 |
| Oak / hardwood | $5.00 – $15.00 |
Prices are 2026 US averages. Actual costs vary by region and supplier.
Recommended Depths for Lumber
| Project / Use Case | Recommended Depth |
|---|---|
| 2×4 (actual: 1.5" × 3.5") | Standard framing |
| 2×6 (actual: 1.5" × 5.5") | Floor joists, walls |
| 2×8 (actual: 1.5" × 7.25") | Floor joists, rafters |
| 4×4 (actual: 3.5" × 3.5") | Posts, fencing |
How to Calculate Lumber Volume
Most landscaping suppliers sell lumber by the cubic yard. To convert your project area to cubic yards, use this formula:
Volume (cu yd) = (Length × Width × Depth) ÷ 27
Our calculator also multiplies your cubic yard result by 0.5 tons/yd³ (the standard density for lumber) to show estimated weight — essential if you are hauling the material yourself or need delivery pricing.
Lumber Calculator: Board Feet Formula Explained
A board foot is a unit of volume equal to 144 cubic inches: a board 1 inch thick, 12 inches wide, and 12 inches long. To calculate board feet for any lumber, multiply thickness (inches) × width (inches) × length (feet), then divide by 12.
Lumber yards price hardwoods by the board foot, while framing lumber is typically priced per piece. Knowing board feet helps you compare prices across different board sizes and spot the best value for your project.
Pro Tips & Insights
1
Lumber is sold by nominal dimensions (2×4) but the actual size is smaller (1.5" × 3.5"). Always use actual dimensions for precise project planning, but board feet are calculated from nominal sizes.
2
One board foot equals 144 cubic inches of lumber. The formula is: (Thickness in inches × Width in inches × Length in feet) ÷ 12.
3
Order 10-15% extra lumber beyond your calculated board feet. This accounts for knots, warping, cutting waste, and boards you will reject at the lumber yard.
4
Pressure-treated lumber costs 30-50% more than standard framing lumber but is essential for any wood that touches the ground or is exposed to weather.
Frequently Asked Questions
How do you calculate board feet?▼
Multiply thickness (inches) × width (inches) × length (feet), then divide by 12. For example, a 2×6 that is 10 feet long: (2 × 6 × 10) ÷ 12 = 10 board feet. Our lumber calculator above does this instantly for any quantity.
What is the difference between nominal and actual lumber sizes?▼
Nominal sizes (2×4, 2×6) are the names lumber is sold by. Actual sizes are smaller due to planing: a 2×4 is actually 1.5" × 3.5", a 2×6 is 1.5" × 5.5". Board feet are always calculated using nominal dimensions.
How many board feet are in a 2×4×8?▼
A standard 2×4 that is 8 feet long contains 5.33 board feet: (2 × 4 × 8) ÷ 12 = 5.33. A 2×4×10 contains 6.67 board feet, and a 2×4×12 contains 8 board feet.
How much does lumber cost per board foot in 2026?▼
Framing lumber (pine/fir) runs $1.50 to $3.00 per board foot in 2026. Hardwoods range from $4 to $15+ per board foot depending on species. Cedar and redwood fall in the $3 to $8 range.
How much extra lumber should I order?▼
Order 10% extra for simple projects with straight cuts, and 15% for projects with many angles, notches, or complex joinery. You will always find boards with knots or warping that need to be rejected.