Read a sawmill tally in board feet
A board foot, abbreviated BF, describes lumber volume: a piece one inch thick, twelve inches wide and twelve inches long contains one board foot. That is 144 cubic inches. Thickness is part of the calculation, so two equally wide and long planks do not have the same tally if one is twice as thick. The unit is useful when comparing hardwood or rough-sawn stock sold by volume rather than by individual length.
Choose the dimensions used for billing
Board feet per piece = thickness in inches × width in inches × length in feet ÷ 12Enter the dimensions the seller uses on the invoice. Rough stock may be tallied using a nominal thickness before surfacing, while your final dressed board is physically thinner. Do not substitute a finished dimension unless that is the agreed billing basis. Metric fields accept millimetres for thickness and width and metres for length. The price field always remains currency per board foot, including when you select metric dimensions.
Ten one-inch planks
A one-inch-thick plank six inches wide and eight feet long contains 1 × 6 × 8 ÷ 12 = 4 board feet. Ten such pieces make a 40 BF tally. At five currency units per board foot, their calculated price is 200. The same dimensions are 25.4 millimetres, 152.4 millimetres and 2.4384 metres. Entering those measurements in metric mode gives the same tally, with a combined geometric volume of approximately 0.0943895 cubic metres.
Handle mixed stock and supplier rounding
This form counts identical pieces. For boards of several widths or lengths, calculate each group separately and add the board-foot totals. Some sawmills round widths, lengths or individual tallies according to their sales policy. This calculator keeps the arithmetic unrounded until display and does not reproduce an unknown commercial grading rule. Defects and offcuts reduce the usable yield even when the purchased tally is correct. Plan the number of pieces around your cutting schedule, and confirm whether surfacing, delivery, tax or minimum charges are included in the quoted price. A geometric tally alone cannot predict the quantity of clear finished components recoverable from a particular stack of lumber.
Frequently asked questions
Is a board foot the same as a linear foot?
No. A linear foot describes length alone; a board foot includes width and thickness. Their relationship changes with the cross-section.
Should I use actual or nominal dimensions?
Use the seller's billed dimensions for a price tally. Use measured dimensions only when calculating actual physical wood volume.
Can I enter a fractional piece count?
No. This tally counts whole identical boards. For a partial length, change the length field instead of entering a fraction of a piece.
Does metric mode change the price unit?
No. The price is always per board foot. Only the dimension fields change to millimetres and metres.
Is waste automatically added?
No. The output is the entered purchase tally. Increase the piece count according to your own cutting plan if more stock is needed.
Last reviewed: 2026-10-05 · How we calculate