Cat's eye colour depends on a variety of factors, including coat colour, breed and health. As with human babies, kitten's eyes are usually blue at birth but by three months of age the pigmentation has matured to leave the growing cat with its permanent eye colour, of which there is a wide spectrum.
1 / 4
At one end of the spectrum there are cats with deep copper-coloured eyes, such as the Persian, some with lighter copper like the Bombay and those with darker orange to yellow-orange, such as the European Shorthair. Then there are the yellow to blue hues at the other end of the spectrum, such as hazel like the British Shorthair, yellow-green or gold as seen in the Turkish Angora, green in the Russian Blue, aqua-blue in Siamese breeds and light blue in the Ragdoll. Of course there are mixes within each breed so that for instance the Maine Coon cat can have either brilliant gold or green eyes.
2 / 4
Genetics plays a strong part in determining cats' eye colour, as it does their coat colour, but the complexity of the inherited colours will show themselves differently in sibling cats. White cats and cats with strong stripe colours often have blue eyes, while tabby cats or those with irregular stripes tend to have green. Purebreds normally have deep orange eyes, while non-pedigrees are more likely to have green eyes.
3 / 4
Paying Attention To Eye Color
If a cat's eyes suddenly seem to turn dark yellow or even brown, it may be suffering from an underlying health problem. Changes in colour like this are often a signal of a build-up of red blood cells in the eyeball. Eye trauma or an eye infection need to be treated immediately and a vet needs to examine the cat to be able to eliminate anything more serious such as feline leukaemia or AIDS.
4 / 4
The Odd Eyed Cat
Occasionally a cat will have eyes that are different colours. The odd-eyed cat will most usually have one blue eye and one green or one yellow and one copper-brown eye. It is due to a condition known as heterochromia, which can result in a complete lack or excess of melanin, the colour pigment. This most commonly affects white-coloured cats but can be found in a cat of any colour, if it possesses extreme whiteness in its genes (the piebald or "whiting" gene).