How do you tell male and female platy fish apart and how do you tell if they are pregnant

Question

How do you tell male and female platy fish apart and how do you tell if they are pregnant

Answer 1

The females have a fan fin at the bottom. The males have a pin looking fin. When the female is pregnant there will be a really dark spot by her bottom. It is called a gravid spot. You will be able to see the bodies and eyes. It is easier to tell on white platys but if you look really closely at the orange ones you can tell.  

Answer 2

If you want to have a few baby livebearers, get two or three fat female you can tell they are females due to their fan shaped anal fin unlike the males elongated gonopodium

It is obvious to tell which female guppies are pregnant as they will have an obvious black "gravid" spot which is the fry's eyes forming inside the mother, this will form just in front of her anal fin. For platies and mollies the only way to tell how far into the pregnancy the fish is, is by seeing how fat they are, platies and mollies which are about to spawn will seem almost square from the back view and will be very swollen in the middle.