A piece of surfaced (sanded smooth) 2×4 lumber actually measures 1½ inches thick and 3½ inches wide. In rough-cut condition, a 2×4 is slightly less than 2 inches thick and approximately 4 inches wide. When wood is milled from a rough to a smooth surface, it loses about ¼-inch from each of its four sides.

What size are 2x4 studs?

Because of this extra milling, a 2×4 no longer measures a full 2 inches by four inches. Instead, a 2×4 is really only 1 1/2″ by 3 1/2″. The same is true of pine. A 1×6, for example, actually measures 3/4″ x 5 1/2″.

What is the length of a 2x4?

Standard 2×4 length 2×4 studs are typically 8 feet long, to match the standard length of a sheet of plywood or drywall. You can also find 2×4 studs that are 92 ⅝” long, which allows builders to account for the thickness of the boards that run along the top and bottom of the wall.