The average to around 4-6 feet. Males tend to be a bit larger. bigger, and longer than the females. Ususally females grow to around 4 feet (this might be because of breeding and all the hard working in laying eggs thus stunning their growth. Males don't need to lay the eggs so they tend to get larger and since they are not the ones carrying the eggs their growth doesn't get stuned as much.)
Good Luck and Happy Herping!