When Do Kittens' Eyes Change Color?

There aren't many things in the world quite as irresistible as a kitten. Those tiny noses, the little cries, and the wobbly walk that comes with their overall lack of coordination top the list of cute features that have us fawning over them, as do those round, cloudy blue eyes that look up at us and the world around them with absolute wonder. Over time, however, many kittens' eye color will lose that blue hue and evolve into the color they will wear into adulthood, but when does that happen? And why does their eye color change?

Bengal kitten
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When does kittens' eye color change?

Kittens undergo a lot of changes in just a short period of time. A kitten's eye color will sometimes change before adulthood, although not this isn't the case for all cats. That change will, of course, fall in its natural order. When kittens are born their eyes are closed to the world around them and stay that way for around 10 days, states the ASPCA, but additional sources claim that this can take up to two weeks. During this time they will also begin to become aware of the sounds around them, and start developing behavioral skills by interacting with their moms and litter mates, says The Humane Society.

In the weeks that follow, kittens will develop their senses even more, namely, their sense of smell, hearing, and their sense of sight. Vet Info states that sometime between three weeks and two months of age a kitten's eyes may begin to change color from a foggy blue to a darker shade. Often, this change can be spotted with the appearance of brownish, amber, yellow, or greenish flecks of color within the iris, or colored part, of your kitten's eyes. Whatever your kitten's eye color may be, week five typically marks the time when their eyesight is totally developed. At this point they will be able to get around on their own without falling over, play with their brother and sisters, pounce on objects, thereby exercising their prey drive, and even stalk objects like other animals in the home, including their litter mates, any people that walk by, and loosely-moving items like a curtain blowing in the wind, or an untied shoestring that may cross their path.

ginger striped kitten climbing up a tree trunk
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Why do kittens' eyes change color?

Like human and canine babies, a cat's eyes start out blue when they are born. Over time, some kittens will undergo a shift in the pigment of their eye color thanks to melanin, which isn't present at birth according to the Fort Lauderdale Eye Institute. Just like in the skin, melanin in the eyes protects the body from UV rays found in sunlight. This is not to say that cats with blue or light eyes aren't protected from the sun in the same way that their copper or brown-eyed counterparts are, it just means that their bodies have less melanin to work with.

Surprised cat muzzle with yellow eyes looks up
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What might a cat’s eye color mean?

While the eye color of many kittens will change over time, the hue that they're left with through their adult years may reveal more about them than some people realize. For example, a cat with mostly white fur and blue eyes is more likely to be deaf than cat with other eye and hair color combinations, feline geneticist Leslie A. Lyons said in a story originally reported by The Sacramento Bee. The outlet went on to explain that white cats with heterochromia, or two different colored eyes, may even experience deafness in the ear which corresponds to their blue eye — meaning, if their left eye is blue and their right eye is green, that cat may be deaf in the left ear.