Calculator Inputs
Example Data Table
| Scenario | Boards | Dimensions | Losses | Usable | Finished coverage |
|---|---|---|---|---|---|
| Small built-in shelves | 12 | 1 in × 6 in × 6 ft | Defects 5%, Waste 12% | ~31 BF | ~41 ft² at 0.75 in |
| Stair treads | 18 | 1.25 in × 8 in × 8 ft | Defects 8%, Waste 15% | ~92 BF | ~74 ft² at 1.25 in |
| Flooring planks | 24 | 1 in × 7 in × 10 ft | Rip 3%, Kerf est, Waste 18% | ~108 BF | ~144 ft² at 0.75 in |
Examples are illustrative and will vary by species, milling, and grading.
Formula Used
- Board feet: BF = (Thickness × Width × Length × Quantity) ÷ 12 (inches, inches, feet).
- Sequential yield: apply each loss factor one after another to avoid double counting.
- Finished area: Area(ft²) = Usable BF ÷ Target Thickness(in).
- Linear footage: Linear(ft) = Area(ft²) ÷ (Finished Width(in)/12).
Kerf and trim are estimated as practical percentages from your inputs.
How to Use This Calculator
- Select your measurement system and enter your board dimensions and quantity.
- If you already know purchased board feet, enter it and leave dimensions as-is.
- Set realistic losses for defects, ripping, waste, and optional shrinkage.
- Choose target finished thickness and width to estimate coverage and linear footage.
- Click Calculate Yield to see results and download reports.
Hardwood Yield Planning Guide
1) What “yield” means in hardwood work
Hardwood yield is the share of purchased rough lumber that becomes usable, dimensioned stock after trimming, ripping, surfacing, and defect removal. In practice, two boards with identical sizes can deliver different usable output because knots, checks, sapwood, and warp force extra cutoffs.
2) Board feet as the purchasing baseline
Most yards price hardwood by board feet (BF). This calculator starts from BF because it captures volume across mixed widths and thicknesses. If you know your invoice total BF, enter it directly to bypass dimension-based estimation and focus on process losses.
3) Defects and grading assumptions
Defect allowance reflects what you must cut around to achieve clean parts. Higher grades typically reduce defect loss, while rustic selections may increase it. For furniture panels, a 5–12% defect factor is common; for clear trim, you may target the lower end with careful selection.
4) Ripping, edging, and layout efficiency
Rip/edging loss covers straightening a reference edge and cutting to finished widths. Narrow parts and heavy layout constraints often increase this loss. Planning your cut list to share widths, keep grain direction consistent, and minimize re-squaring can materially improve yield on larger builds.
5) Kerf and the hidden cost of many cuts
Kerf is the material turned into sawdust by each cut. While a single rip is small, repetitive processing adds up. Thin-kerf blades help, but the biggest wins come from reducing unnecessary cuts, grouping identical parts, and leaving safe machining margins without excessive overcutting.
6) Trim allowance and end checking control
End checks and handling damage are frequent on longer boards. A trim allowance per end is a practical way to budget for squaring. If you store lumber for acclimation, include a slightly larger trim allowance to address minor splits that appear as moisture equalizes.
7) Finished thickness, coverage, and linear footage
After usable BF is estimated, coverage is calculated from your target finished thickness. Thinner stock yields more area from the same volume, while thicker builds reduce coverage. Linear footage then depends on finished width, which is helpful for flooring, planks, face frames, and rails.
8) Using yield to protect budget and schedule
Yield forecasting turns “guess and buy extra” into a controlled plan. Start with realistic losses, then compare the usable BF and area to your project requirements. If you are close to the minimum, increase waste slightly to protect deadlines, or select higher grade boards to reduce defects.
Pro tip: track actual yield on a few jobs and update your default loss settings for future estimates.
FAQs
1) Why does the calculator apply losses sequentially?
Sequential reductions avoid double counting. Defects are removed first, then ripping, kerf, trimming, and general waste. This mirrors real processing steps and usually produces a more realistic usable estimate than simply adding percentages together.
2) What should I use for general waste?
For straightforward parts, 10–15% is typical. Complex layouts, curved pieces, or strict color matching may need 18–25%. Use your past job history whenever possible, then adjust upward if the project has tight deadlines.
3) How do I choose a defect percentage?
Base it on grade and how “clear” parts must be. Clear trim and visible panels often require lower defect loss with better selection. Rustic work can tolerate more character, but hidden warp or checks may still increase cutoffs.
4) Do I need to enter kerf if I already enter rip loss?
Kerf captures the sawdust volume from cuts, while rip loss captures extra width removed for straight edges and sizing. If you don’t want a separate kerf estimate, set kerf to zero and include it inside rip loss.
5) How is finished area computed from board feet?
One board foot equals 144 cubic inches. At a target thickness, area is usable board feet divided by that thickness (in inches). This converts volume into surface coverage, useful for flooring, panels, and cladding estimates.
6) When should I use a shrinkage allowance?
Use it when lumber moisture content may change after purchase, or when projects span seasons. A small allowance (0–3%) can help protect fit-up. For acclimated, kiln-dried stock used promptly, shrinkage may be negligible.
7) Why does my usable result look low for short boards?
Trim allowance becomes a larger percentage of total length when boards are short. If your lumber is already squared and defect-free, reduce trim and defect settings. For reclaimed stock, keep higher allowances to avoid surprises.
Accurate yield estimates keep budgets, schedules, and waste controlled.