How to tell a kitten's age by their teeth, weight, and eyes
You can estimate a kitten's approximate age by looking at three things: whether their eyes are open (they open around the second week), which teeth have come in (baby teeth appear from 3 weeks and are all in between 6 and 8), and how much they weigh (around 1 kg / 2 lb at 8 weeks). It is only an estimate: your vet can refine it with an exam.
Quick answers
- Eyes still closed?Less than about 2 weeks: eyes open between roughly 8 and 12 days.
- Blue eyes and rounded ears?About 2 weeks.
- Front baby teeth peeking out?About 3 weeks.
- All baby teeth in?Between 6 and 8 weeks.
- Weighs around 1 kg (2 lb)?About 8 weeks.
- Teeth changing?Between 3 and 7 months.
In this guide
Why knowing their age matters
Age decides what they eat, how often, when deworming starts, and when they get their vaccines. A 2-week-old kitten needs bottle feeding and warmth; an 8-week-old already eats kitten food.
If you found kittens outdoors, Alley Cat Allies reminds you not to separate them from their mother: watch from a distance for a few hours, because she usually comes back.
Age by eyes and ears
- Newborn: eyes closed and ears folded down.
- Around 1 week: ears start to open.
- Between 8 and 12 days: eyes open on their own. Never try to open them.
- 2 weeks: eyes fully open and blue; small, rounded ears.
- 3 weeks: ears already point upward, like a miniature adult cat.
- Toward 2 months: the adult eye color may start to show.
Age by teeth
Kittens are born with no visible teeth. They have 26 baby teeth and, as adults, 30 permanent ones.
| Approximate age | What you see in the mouth |
|---|---|
| 3 weeks | Incisors peek out (the front little teeth). |
| 4 weeks | Canines come in. |
| 5 weeks | Premolars start to come in. |
| 6โ8 weeks | All baby teeth are in. |
| From 3 months | They start to change: first the incisors. |
| Toward 5 months | Permanent canines come in. |
| 6โ7 months | Most already have all 30 adult teeth. |
VCA places the start of tooth change between 10 weeks and 6 months in one article and "from 3 months" in another: these are ranges, not exact dates.
Age by weight
Kitten Lady, a kitten rescue organization, gives these average weights:
| Age | Average weight |
|---|---|
| Newborn | 75โ150 g |
| 1 week | 150โ250 g (roughly double birth weight) |
| 2 weeks | 250โ350 g |
| 3 weeks | 350โ450 g |
| 5 weeks | 550โ650 g |
| 6 weeks | 650โ750 g |
| 8 weeks | around 900 g (2 lb) |
Weight varies by breed, litter, and feeding, so use it together with teeth and behavior, not alone.
Age by what they do
- 1โ2 weeks: barely move, sleep almost all the time, and depend on their mother to eat and eliminate. We cover this in how much do kittens sleep.
- 2 weeks: walk unsteadily.
- 3 weeks: walk more steadily, explore, and start using the litter box. See litter train your kitten.
- 4 weeks: run and play with siblings.
- 5โ6 weeks: weaning starts with wet food.
- 8 weeks: weaned, play with good coordination.
Signs to see the vet
Take your kitten to the vet as soon as possible if:
- They are so small that their eyes are still closed or they cannot stay warm on their own: they need special care.
- They are not gaining weight day to day, are weak, or will not eat.
- They have diarrhea or vomiting (see kitten with diarrhea).
- You see two teeth in the same spot or a crooked bite: they may have a retained baby tooth.
Create a Nekolife account
Did you adopt or rescue a kitten and not know their age? Share a photo with other caregivers and keep the guides at hand.
Create account โ It's free and you'll come right back here.
Frequently asked questions
How do I know if my kitten is under a month old?
If they have no teeth or only the front ones, and walk unsteadily, they are probably under 4 weeks.
At what age does a kitten open their eyes?
Between about 8 and 12 days. By 2 weeks they are usually fully open.
How much does a 2-month-old kitten weigh?
Around 900 g (2 lb), though it varies by breed and kitten.
When do kittens change their teeth?
From about 3 months, and by 6โ7 months most have all 30 adult teeth.
Do kittens have blue eyes?
They are all born with blue eyes; adult color appears over time and may show toward 2 months.
Caring for a cat? Keep their health in your pocket
Register your cat on Nekolife to track vaccination history, weight, and get advice from loving cat parents.
- Vaccine & weight records
- Supportive cat community
- Earn Meow Points & badges
Related pages
Sources
- "How to Determine a Kitten's Age". Kitten Lady. kittenlady.org
- "Kitten Progression: At-a-Glance Guide". Alley Cat Allies. alleycat.org
- "Persistent Deciduous Teeth (Baby Teeth) in Cats". VCA Animal Hospitals. vcahospitals.com
- "How To Tell If Your Kitten Is Teething". VCA Animal Hospitals. vcahospitals.com
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