Wikipedia's page on lumber[1] is a bit more rigid: Today, a "2×4" board starts out as something smaller than 2 inches by 4 inches and not specified by standard

Wikipedia's page on lumber[1] is a bit more rigid: Today, a "2×4" board starts out as something smaller than 2 inches by 4 inches and not specified by standards, and after drying and planing is reliably 1 1⁄2 by 3 1⁄2 inches (38 mm × 89 mm). 1: https://en.wikipedia.org/wiki/Lumber#North_American_softwoods https://en.wikipedia.org/wiki/Lumber#North_American_softwood...