Calculator Inputs
Formula Used
Board feet measures lumber volume. One board foot equals a board that is 1 inch thick, 12 inches wide, and 12 inches long.
- BF = (Thickness(in) × Width(in) × Length(ft)) ÷ 12
- BF = (Thickness(in) × Width(in) × Length(in)) ÷ 144
Total board feet for a line item is BF_each × Quantity. Waste-adjusted total is Total_BF × (1 + Waste%/100).
How to Use This Calculator
- Enter your waste factor and optional price per board foot.
- Add one or more line items for each board size.
- Fill thickness, width, length, unit, and quantity.
- Click Calculate Board Feet to view results above.
- Use the download buttons to export a CSV or PDF report.
Example Data Table
| Thickness (in) | Width (in) | Length (ft) | Qty | BF / Piece | Total BF |
|---|---|---|---|---|---|
| 2 | 6 | 8 | 10 | 8.000 | 80.000 |
| 1 | 4 | 10 | 12 | 3.333 | 40.000 |
| 0.75 | 12 | 6 | 6 | 4.500 | 27.000 |
| Total (no waste) | 147.000 | ||||
Example totals exclude waste. Add waste to match your buying plan.
Board Feet as a Universal Lumber Language
Board feet convert rough and finished boards into a single volume measure that suppliers, sawmills, and estimators understand. Using one unit reduces confusion when you mix nominal and actual sizes, different species, or varied stock thicknesses on the same takeoff. It also supports price comparisons across yards. The calculator applies the 1-inch by 12-inch by 12-inch definition, so results stay consistent across trades.
Handling Nominal Sizes and Planed Lumber
Many boards are sold by nominal dimensions, yet arrive planed to smaller actual sizes. For accurate material cost forecasting, measure actual thickness and width when possible, especially for interior carpentry and cabinetry. When estimating framing or temporary works, nominal values may match how the supplier prices bundles. Record which basis you used, because a small dimension difference can shift totals on large quantities.
Waste, Defects, and Practical Allowances
Board-foot totals describe theoretical volume, not usable yield. Add a waste factor for knots, checking, wane, and cutting losses. A 5–10% allowance is common for straight framing, while 10–20% may suit tight joinery, curved layouts, or selective appearance grades. Consider moisture movement, end trimming, and damaged handling during transport. Document your assumptions for repeatable bids and clear change-order discussions.
Multi-Item Takeoffs for Projects
Construction lists rarely contain a single board size. Break down beams, joists, decking, blocking, and trim into line items, then sum totals for purchasing. Grouping by thickness and width helps match available stock and minimizes overbuying. Exporting a line-item report improves coordination with procurement and site crews.
Using Results for Cost and Logistics
Once you know board feet, multiply by unit price to estimate lumber cost, and convert to truckloads or pallets for delivery planning. Compare totals with package quotes, verify lead times for specialty species, and revise waste based on cutting plans. Use the item list to stage deliveries by phase, reducing site congestion and weather exposure. Consistent board-foot reporting strengthens controls.
FAQs
What is one board foot?
One board foot equals a volume of 1 inch thick, 12 inches wide, and 12 inches long. It is a standardized way to compare lumber quantities across different board sizes and lengths.
Should I use nominal or actual dimensions?
Use actual measured thickness and width for precision, especially in finish work. Use nominal sizes only when your supplier prices strictly by nominal dimensions and your estimate must match that pricing basis.
How do I convert inches to feet in the calculator?
Enter thickness and width in inches. For length, choose inches or feet using the unit selector. The calculator converts length to inches internally so the board-foot formula stays consistent.
What waste percentage is reasonable for ordering?
For general framing, many estimators add 5–10% waste. For cabinetry, selective grades, or complex cuts, 10–20% is common. Adjust for defects, cut lists, and site handling conditions.
Can I calculate multiple board sizes at once?
Yes. Add multiple line items, each with its own thickness, width, length, unit, and quantity. The tool totals all items, then applies optional waste to provide both net and buying quantities.
How can I use the CSV or PDF export?
Use exports to share takeoffs with procurement, attach estimates to bids, or keep project records. CSV works well for spreadsheets, while PDF is convenient for printing, email, and approvals.