How do you tell the difference between a girl and a boy frog?

It is almost impossible to tell on appearance. Females are usually larger but there is much overlap. It is usually only the males that call but just because it is silent doesn't mean it is a female. Sorry i had to eddit! Is is missing alot! You can tell the difference, by simply flipping the frog over, and if it has a dark stomach then it is a boy if it has a plain stomah it is a girl! And that is how you tell the difference!