Ball Python Hatchlings are approximately 10 inches and more. Adult Size Femal Ball Python averages length of 3 to 5 feet long. Male Ball Pythons average 2 to 3 feet long.This is a species in which mature females are typically distinctly larger than the males. A 5 foot or larger ball python is considered large, although ball pythons with lengths of 6 feet and more have been reported.