How to Determine Board Footage

Understanding board footage is not as tough as you think. Use this simple guide to understand more about how to calculate board feet, as well as determining lumber thickness.

What is a Board Foot?

A board foot is the unit of volume used to measure hardwoods. Since hardwoods are sold in a variety of lengths, widths and thicknesses, it is simpler to have a kind of measure that can account for all of those variables at once, like volume. Board footage is a good tool to measure volume.

12″ long x 12″ wide x 1″ thick = 144 cubic inches

Armed with a tape measure, calculator and this knowledge, you can tackle any board foot calculation on the spot. But what happens the day you leave the shop and forget your calculator? Well, you could borrow one from us. Or just use this woodworker rule of thumb: 4/4 board, 8 ft. Long and 6″ Wide = 4 Board Feet

Determining Lumber Thickness

When buying hardwoods, you won’t see lumber thickness marked in inches, but instead the convention is to use a measurement in quarters. For example, a 1 inch thick board is typically written as 4/4.

One thing to keep in mind is that lumber is sawn and then dried so the board that started out 4/4 inches will be closer to 7/8″ (.875 inches) – and that thickness is before any type of surfacing is done.