Instructions
Observe the color of the face on your mature cockatiel. Males tend to have a bright yellow face with a brightly-colored orange patch on the cheek; females will have a grey or pale yellow face with a duller patch of orange on the cheek.
Look on the underside of the bird's feathers. Males will have a sold color underneath their wings and tail feathers, while females will have spots underneath.
Pay attention to hear, after nine months, if your cockatiel is singing or not. A male will start singing at nine months and a female will not.
Examine your nine-month old cockatiel to see if the bird is molting. A female cockatiel will begin to molt into her adult feathers at around nine months and a male bird will not.
How to Determine Gender of Cockatiels
You must identify the gender of your cockatiels if you want to breed them or place two of the same gender in a cage so they won't breed. You can also give your birds appropriate names if you know their gender. The only way to determine the cockatiels' gender correctly is to wait at least nine months before attempting to determine if they are male or female.