Start with the unit on the price tag
A price per board foot ($/BF) applies to a unit of lumber volume. A price per linear foot applies only to length, usually for a specified cross-section. A price per piece applies to the whole board. Do not compare these numbers without first matching the unit and board dimensions.
MBF means one thousand board feet in lumber pricing. A quoted $1,800 per MBF is $1.80 per BF: $1,800 ÷ 1,000. Confirm the quote’s unit rather than assuming a large number is a per-board price.
A purchasing example
A supplier quotes $6.50 per BF, and confirms that your four boards will each be tallied as 1 inch × 6 inches × 8 feet. Their combined tally is 16 BF, so the lumber estimate is 16 × $6.50 = $104. Ask about tax, delivery, minimums and other charges before treating that as the checkout total.
If the same lumber is sold by the piece instead, use that actual per-piece price. A geometric volume estimate does not override the supplier’s sales unit.
Measured size and tally size can differ
Surfacing removes material. A supplier may base its lumber tally on rough thickness or another stated convention rather than the final thickness you measure. A nominal dimension is also not necessarily the finished dimension. Before estimating a bill, ask: “Which thickness, width and length will you use for this tally?”
For physical volume, use measured dimensions. For a price estimate, use the confirmed tally inputs. Keep the two calculations separate and label them so a smaller finished board does not look like a formula error.
Ask these questions before you buy
- Is the quote per BF, per MBF, per linear foot, or per piece?
- Is the tally based on rough or surfaced thickness?
- How are irregular widths, lengths, and fractional dimensions measured?
- Does the seller round each board, the total tally, or both?
- Are there minimum quantities, processing fees, delivery charges, or taxes?
- How much extra material does your particular cutting plan require?
Compare a mixed shopping list
Use one row per different board size in the board foot calculator. Use separate calculations for lumber with different prices per BF. The optional price field applies one rate to the whole list; it does not average prices or account for species, grade, or supplier discounts.
Print the tally and compare it with the supplier’s quote. The calculator preserves unrounded volume for its cost calculation. Its displayed number is rounded to four decimals; that may differ from a commercial tally rounded to other increments.
Volume does not guarantee a cutting layout
Two boards with equal volume are not interchangeable when the project needs a long, wide, clear piece. Required lengths, grain direction, defects, kerf, and joinery determine usable yield. Check those constraints separately before reducing a purchase to a board-foot total.
Reference and method
For broader wood-property and lumber context, see the USDA Forest Products Laboratory’s Wood Handbook (2021). The examples here are original arithmetic examples; supplier-specific billing rules must be confirmed with the seller. See how WoodCutMath calculates results.