While it's difficult to tell the difference between young male and female Indian ringneck parrots, by the time Psittacula krameri matures there's a simple way to distinguish gender. While the native sub-Saharan parrot was green, breeders have created Indian ringneck parrots in various hues, including blue.
The Telltale Rings
While this colorful bird is named the ringneck, only the male develops the telltale rings. A thin black ring extends from the bill to the eyes, while a thicker ring starts at the lower part of the bill, thinning out as it reaches the neck where it joins with a rose-colored band present on the neck. While females don't have the black rings, they might have pinkish neck bands.
Since Indian ringneck parrots don't reach sexual maturity -- and ring development -- until the age of 2 or 3, you might have to send feather or blood samples to a lab for DNA testing if it's important to know the gender earlier. Young birds all tend to look like females, although their coloring isn't as bright as the adult hen.