Board Feet Calculator - Calculate Lumber Volume and Cost
Free board feet calculator. Instantly calculate lumber volume and cost. Enter thickness, width, length, and quantity for accurate estimates.
Lumber Pieces
Dimensions
Quick Size & Species
About This Calculator
How to Calculate Board Feet
Measuring Tips
- Measure thickness and width in inches, length in feet
- Use actual dimensions, not nominal sizes (a 2×4 is actually 1.5×3.5)
- Round up to the nearest inch for rough lumber
- For tapered boards, average the widths at both ends
- Always add 10-15% for waste and defects
Common Lumber Sizes
| Nominal | Actual | BF per 8ft |
|---|---|---|
| 1×4 | 0.75×3.5 | 2.33 |
| 1×6 | 0.75×5.5 | 3.67 |
| 2×4 | 1.5×3.5 | 4.67 |
| 2×6 | 1.5×5.5 | 7.33 |
| 2×8 | 1.5×7.25 | 9.67 |
Tips for Buying Lumber
- Inspect each board for warping, cupping, and defects
- Buy extra for waste, especially with hardwoods
- Consider moisture content for your project type
- Hardwood is sold by the board foot, softwood by the piece
- Prices vary significantly between rough and surfaced lumber
Frequently Asked Questions
How do you calculate board feet?
Board feet = (Thickness in inches × Width in inches × Length in feet) ÷ 12. For example, a 2×6 board that is 8 feet long: (2 × 6 × 8) ÷ 12 = 8 board feet. Multiply by the quantity to get total board feet.
What is the difference between board feet and linear feet?
Linear feet measures only the length of a board, while board feet measures volume (thickness × width × length). A 1×6 board that is 8 feet long is 8 linear feet but only 4 board feet. Board feet is the standard unit for pricing hardwood lumber.
How much does a board foot of lumber weigh?
The weight varies by wood species. Oak weighs about 4.5 lbs per board foot, maple about 4.2 lbs, pine about 2.5 lbs, and walnut about 3.8 lbs. Weight depends on moisture content and specific gravity of the wood.
What is the standard board foot price for hardwood?
Hardwood prices vary by species and grade. Common prices: Red Oak $4-8/bf, White Oak $6-12/bf, Maple $5-10/bf, Walnut $8-15/bf, Cherry $6-12/bf. Prices vary by region, supplier, and current market conditions.