Another thing to remember, if you know bolt size, you can figure wrench size, and vice versa, on non metric hardware.
On standard hardware, it’s bolt size times 1.5 for wrench size ie: 1/2” bolt, times 1.5 (2/4 + 1/4 = 3/4” bolt head)
Usually stud and hd nuts, it’s 1.5 x stud size plus 1/16...