Price per board foot, per linear foot and per board
One price, said three ways. A board's price is the price per board foot times the board feet in it; a linear foot's, the price per board foot times the board feet in a foot. A 5/4×10 board 8 ft long holds 1¼ × 10 × 8 ÷ 12 = 8.333 board feet and 1.042 in each foot, so at $4.15 a board foot it is $34.58 a board and $4.32 a linear foot. A thousand board feet — MBF, the unit a yard quotes a truckload in — is $4,150.
Turn it round with "The price is": type $34.58 per board and the page says $4.15 a board foot. That is how to compare a price per piece with a price per board foot, or two widths with each other: a 2×4×8 at $4.00 is 75¢ a board foot over its 5.33 board feet.
Which board feet you are paying for
The board feet in these prices are nominal: a yard's price per board foot is per board foot of the size on the tag (PS 20, the softwood standard). The 5/4×10 above is dressed to 1 in by 9¼ in: the $34.58 buys 6.17 board feet of wood, and the answer prints both figures. For hardwood, choose a hardwood measure: its price is per board foot of the yard's tally.
With more than one size on the page, a price per linear foot or per board is read from the first board, the one the price lines name, and the board feet price it comes to is applied to the rest. A list of mixed sizes at one price per piece is not one rate; price each size on its own page.
What the list costs
Add boards and a waste percentage and the page prices the list: the boards a yard sells, at the price you typed, before and after waste. Prices change by species, grade and week: the $4.15 this page opens with is the worked example above, not a price to buy at. Type your yard's.