Actual Dimensions (wood)

This is the term used to reference the exact dimensions of standard lumber and their measurements in inches. “Actual dimensions” goes hand-in-hand with “nominal dimensions”, which is used to describe a piece of wood as it is first cut (rough cut) before getting planed and sanded down to its actual dimension. Lengths of wood pieces are always referred to separately from wood dimensions, such as an 8′ 2 x 4 (two-by-four).

So, what are actual dimensions of standard lumber and wood pieces? Measurements below are listed by nominal dimensions first, as these measurements are what are commonly known and used when referring to these wood sizes.

• “1 x 2″ = 3/4″ thick x 1 1/2″ wide (19 mm × 38 mm)
• “1 x 3″ = 3/4″ thick x 2 1/2″ wide (19 mm × 64 mm)
• “2 x 4″ = 1 1/2″ thick x 3 1/2″ wide (38 mm × 89 mm)
• “2 x 6″ = 1 1/2″ thick x 5 1/2″ wide (38 mm × 140 mm)
• “4 x 4″ = 3 1/2″ thick x 3 1/2″ wide (89 mm × 89 mm)
• “6 x 6″ = 5 1/2″ thick x 5 1/2″ wide (140 mm × 140 mm)

Less common wood sizes’ actual dimensions

• “1 x 4″ = 3/4″ thick x 3 1/2″ wide (19 mm × 89 mm)
• “1 x 6″ = 3/4″ thick x 5 1/2″ wide (19 mm × 140 mm)
• “1 x 8″ = 3/4″ thick x 7 3/4″ wide (19 mm × 184 mm)