How to use
- Enter each line’s thickness, width, length and quantity. Choose the unit beside each dimension.
- Mark dimensions Actual or Nominal. The marker describes your inputs; it does not convert nominal sizes to actual sizes.
- Choose a price per board foot, cubic metre or piece for each line and enter a whole-piece allowance.
- Review board feet, volume, total length, whole pieces and cost before comparing the result with the supplier’s measurement rules.
Calculation method
Volume per piece = thickness × width × length. One board foot is 144 cubic inches. Board feet = cubic-inch volume / 144. Each line’s purchase count is round up(quantity × (1 + allowance / 100)); different lines are rounded independently. Cost uses that line’s purchased pieces and either its price per piece or its entered volume price. Line costs are rounded to cents and summed.
Worked example
Four pieces with actual entered dimensions 1 in × 6 in × 8 ft total 16 board feet and 32 ft of length, or 0.037755795456 m³. At 5 USD/BF they cost 80 USD. A 10% whole-piece allowance buys five pieces: 20 BF and 100 USD. Changing the label to Nominal preserves the same arithmetic but means the volume is based on nominal inputs.
Assumptions and limits
Nominal dimensions are not automatically converted using a sizing table. The result can differ from a supplier’s board-foot grading or billing convention. This is not a cut-list optimizer and does not assess strength, span, moisture, defects or structural suitability. Different lengths or cross-sections need separate lines. Tax, transport and machining are excluded.
Units, prices and saved estimates
Physical values are stored internally in metres, square metres, cubic metres or kilograms as appropriate. Changing measurement units converts their display; choosing a currency changes its label without applying an exchange rate. Purchase quantities use unrounded calculations. Money is shown to two decimal places.
Edits can be saved in this tab. Optional device saving lasts seven days after the last save. Copy, TXT download and a separate printable report use the current valid estimate. Delete draft removes saved inputs without resetting the visible form. The privacy choices page can remove all calculator drafts.
For practical measurement decisions, read understanding lumber dimensions and board feet.