How Old Is My Kitten? A Kitten Age Chart

You can estimate a kitten's age from three clues: eyes, teeth and weight. Closed eyes usually mean under about 10 days. Baby teeth start at 2 to 4 weeks, and adult teeth at 4 to 7 months.

The kitten age chart below lines up each milestone week by week. Use it for a good first guess, then let your vet confirm, because every kitten grows at a slightly different pace.

Kitten age chart: what changes week by week?

This chart draws on the developmental milestones in Susan Little's review of orphaned kitten care in the Journal of Feline Medicine and Surgery, Merck's guide to dental development, and the AAHA/AAFP Feline Life Stage Guidelines.

Age	What you'll see
Birth to 3 days	Eyes and ears sealed shut. The umbilical cord stump is still attached and usually falls off around day 3.
1 to 2 weeks	Eyelids open, on average at 7 to 10 days. Ear canals open around day 9. Crawling begins.
2 to 3 weeks	First wobbly steps. The first tiny front teeth may start to show.
3 to 4 weeks	Baby incisors and canines come in. She can pee and poop on her own and can learn to lap from a saucer.
4 to 6 weeks	Adult eye color settles in, and hearing becomes fully functional. Baby premolars arrive at 5 to 6 weeks.
6 to 9 weeks	Weaning is usually finished. She chews dry kitten food, plays hard, and is deep in her socialization window.
About 12 weeks	Play with other cats is at its peak.
4 to 7 months	Adult teeth push out the baby teeth.
12 months	The kitten life stage ends at one year, by the AAHA/AAFP definition.

Treat each row as a range. Little's review gives most milestones as averages, and Merck notes that tooth timing varies a lot between individual cats.

How can I tell a kitten's age from its eyes and ears?

For a very young kitten, the eyes are the quickest clue. Little's review puts eyelid opening at 7 to 10 days on average. If the eyes are still sealed, she is almost certainly under two weeks old.

The ears tell a similar story. The ear canals open at about 9 days, though hearing doesn't fully work until 4 to 6 weeks.

Here's a detail many people don't expect. The eye color you see in the first weeks isn't final. Little's review places adult iris color at 4 to 6 weeks, so the shade can still shift after the eyes first open.

Vision takes time as well. The blink-and-flinch reflex vets test with a hand movement appears at around 28 days or later, and normal vision is in place by about 30 days.

One more clue for the tiniest kittens. The umbilical cord stump usually falls off at about 3 days, so a kitten who still has one is only a few days old.

How can I tell a kitten's age by its teeth?

Teeth are the most reliable clue from about three weeks onward. Merck's veterinary manual explains that cats have two sets: 26 baby teeth and 30 adult teeth.

• No teeth at all: likely under 2 weeks.
• Tiny front teeth (incisors) appearing: 2 to 4 weeks.
• Small, needle-sharp canines: 3 to 4 weeks.
• Baby premolars, the teeth behind the canines: 5 to 6 weeks.
• Larger adult teeth replacing baby teeth: 4 to 7 months.

To look, lift the lip gently at the side of the mouth while she's calm and supported. A few seconds is enough. Never pry the jaw open.

Between about 6 weeks and 4 months, she has her full set of baby teeth, so teeth narrow the range less in this stretch. That's where weight and behavior help.

If you spot a baby tooth on the floor around five or six months, don't worry. That's the adult set arriving, right on Merck's timeline.

How much should a kitten weigh?

A newborn domestic shorthair or longhair kitten weighs about 90 to 110 g, according to Little's review. That's roughly the weight of a stick of butter. Breed matters, from about 73 g for a Korat to 116 g or more for a Maine Coon.

In the first weeks, steady gain matters more than any single number. Merck puts normal growth at 50 to 100 g a week, and Little's review gives 10 to 15 g a day.

A small dip on day one, up to 10% of birth weight, is normal.

A digital kitchen scale that reads in grams makes this easy. Little recommends weighing a hand-raised kitten twice a day for the first two weeks, then daily until weaning.

For older kittens, weight alone is a rough guide to age, because kittens grow at different rates. A 2022 study in PLOS ONE built growth charts for domestic shorthair kittens from 8 to 78 weeks old, much like the charts used for children.

The useful finding was about direction. Kittens who crossed upward through the chart lines tended to be overweight by early adulthood, and those who crossed downward tended to be underweight. Your vet can plot your kitten's weight over a few visits.

What should my kitten be doing at each age?

Behavior fills in the gaps between the physical clues. Little's review notes that kittens under three weeks spend most of their time asleep and are quiet when warm, well fed and healthy.

Until about three weeks, kittens can't pee or poop on their own, so the mother licks them to stimulate it. A kitten that age without a mother needs kitten milk replacer and help after every meal.

From about four weeks, Little recommends offering a shallow litter box with low sides. Our guide on how to litter train a kitten walks through the setup.

Weaning onto kitten food can begin at 3 to 5 weeks, the AAHA/AAFP guidelines say, and Little notes that most kittens can chew dry food by 5 to 6 weeks. For what to put in the bowl next, see what to feed a kitten.

Socialization runs alongside all of this. The AAHA/AAFP guidelines describe a sensitive window that opens as early as 2 to 3 weeks and may be closing by 9 to 10 weeks. They suggest 30 to 60 minutes a day of pleasant time with people.

Call your vet promptly if your kitten:

• stops gaining weight, or loses it
• feels cold to the touch
• won't nurse or eat
• cries constantly, seems restless, or feels limp and floppy
• is under four weeks old and has no mother caring for her

Little's review flags the first two weeks and the weeks around weaning as the most delicate times, and advises prompt veterinary attention for any change from normal.

Questions new kitten parents ask

How can I tell how old a kitten is?

Check the eyes, the teeth and the weight, then compare them with the kitten age chart above. Little's review says that when the birth date is unknown, vets estimate age the same way, from body weight and developmental milestones.

How old is a kitten when its eyes open?

On average, 7 to 10 days. The color will keep changing until about 4 to 6 weeks.

When do kittens get their adult teeth?

Merck puts it at around 4 to 7 months. You may find a lost baby tooth in that window, which is normal.

When is a kitten no longer a kitten?

The AAHA/AAFP Feline Life Stage Guidelines define the kitten stage as birth to one year. Kitten growth charts run to 78 weeks, so some cats are still filling out a little after their first birthday.

How old should a kitten be before it leaves its mother?

Weaning usually finishes between 6 and 9 weeks, Little's review notes. Ask your vet or shelter about the right timing for your kitten, and see our new kitten checklist before she comes home.

Sources

• Little S. Playing Mum: Successful management of orphaned kittens. Journal of Feline Medicine and Surgery, 2013
• Merck Veterinary Manual: Dental Development of Cats
• Merck Veterinary Manual: Management of the Neonate in Dogs and Cats
• Quimby J, et al. 2021 AAHA/AAFP Feline Life Stage Guidelines. Journal of Feline Medicine and Surgery, 2021
• Salt C, German AJ, Henzel KS, Butterwick RF. Growth standard charts for monitoring bodyweight in intact domestic shorthair kittens from the USA. PLOS ONE, 2022

This article is for general information and is not veterinary advice. Talk to your vet about your own cat — they know the animal in front of them.