Board Foot to Linear Foot

How to measure

Name size or dressed size

A board foot uses thickness and width in inches. Nominal softwood is billed by the name: a 2x6 is 2 inches by 6 inches, even though the dressed stick measures about 1 1/2 by 5 1/2. Choose Nominal when the price is per board foot of that name. Choose Actual when you measured the dressed face, or when you are pricing a section that has no name size. The USDA Wood Handbook records width and thickness as the nominal size for this kind of conversion, so the nominal basis is the one that matches a board-foot price.

Thickness and width

Pick a listed size, or choose Custom and type both dimensions. Thickness and width must each be from 1/4 inch to 24 inches. A 4/4 board is 1 inch thick, and the 1x6 preset is that thickness with a 6 inch face. On a listed size the page fills both dimensions. Switching from Nominal to Actual replaces them with the dressed inches, such as 1 1/2 by 5 1/2 for a 2x6. Custom keeps the numbers you type, including a fraction.

Quantity and price

Board feet to linear feet takes the board-foot quantity and returns the length to order. Linear feet to board feet does the reverse, turning a length into the volume a yard would bill. The optional price follows the quantity you typed. A price per board foot becomes a price per linear foot, and a price per linear foot becomes a price per board foot. Leave the price blank when you only need the length. This page does not add waste and does not round up to a stock length.

Formula

Board feet per linear foot equal thickness in inches, times width in inches, divided by 12. Linear feet equal the board feet divided by that rate. Board feet equal the linear feet times the same rate. Dollars per linear foot equal dollars per board foot times thickness times width, divided by 12. The reverse divides the linear-foot price by the rate.

Nominal size uses the name, so a 2x6 stays 2 by 6 after the mill dresses it. Actual size uses the dressed inches. Record width and thickness as the nominal size when you are matching a board-foot price.

A 4/4 by 6 inch board at $5.00 per board foot is $2.50 per linear foot, so 1 board foot of that size is 2.00 linear feet. One linear foot of a nominal 2x6 is 1.00 board foot.

Common mistakes

• Using the dressed 1 1/2 by 5 1/2 for a nominal 2x6 board-foot price.
• Treating 4/4 as something other than 1 inch of rough thickness.
• Expecting the page to round the length up to an 8, 10, or 12 foot stick.
• Leaving the basis on Actual after copying a price that was quoted per nominal board foot.