[jonsen]

I genuinely hate to go and measure my lumber but anyway I just did:

Unplaned 2x5 measures exactly 2" x 5" Planed 2x3 measures 1 15/16" x 2 13/16" Planed 2x4 measures 1 7/8" x 3 3/4"

I'm in Norway. Apparently it's country specific.

[jononor]

In Norway construction lumber is usually specced in mm, e.g. 48x98mm, which is smaller than 2*4 inches. People still call it 2x4 though...