How old is my kitten?
How old is my kitten? Weight gives a good first guess, because healthy kittens gain about 1 lb a month. Add what you can see of the teeth, eyes, ears and walking to narrow the estimate, then check the care notes for that age.
Free calculator · Based on vet sources
Kitten age chart
| Age | Typical weight | What you’ll see |
|---|---|---|
| Newborn to 1 week | 3–5 oz (90–150 g) | Eyes closed, ears folded, umbilical cord may still be attached |
| 1–2 weeks | 5–9 oz (150–250 g) | Eyes open between 7 and 14 days, always blue at first |
| 2–3 weeks | 9–12 oz (250–350 g) | Ears unfold, baby incisors start, first wobbly steps |
| 3–4 weeks | 12–16 oz (350–450 g) | Baby canines appear, walking and starting to play |
| 4–5 weeks | 1–1.2 lb (450–550 g) | Premolars coming in, steadier on their feet, starts using a litter box |
| 5–6 weeks | 1.2–1.4 lb (550–650 g) | Running and pouncing, eating wet food |
| 6–7 weeks | 1.4–1.7 lb (650–750 g) | Full set of baby teeth, eye color may start to change |
| 7–8 weeks | 1.7–2 lb (750–900 g) | Confident, playful, fully weaned |
| 3 months | About 3 lb (1.4 kg) | Adult eye color settling, adult incisors may start |
| 4 months | About 4 lb (1.8 kg) | Adult teeth coming in, baby teeth falling out |
| 5 months | About 5 lb (2.3 kg) | Most adult teeth in, growth starts to slow |
| 6 months | 5–6 lb (2.3–2.7 kg) | Full set of adult teeth by 6–7 months |
Kitten weight by age varies with breed, litter size and health. Strays and orphaned kittens are often small for their age, so teeth and milestones can be more reliable than the scale.
Kitten teeth by age
Teeth are one of the best clues. Gently lift the lip with a clean finger. Baby incisors, the tiny front teeth, come in at 2 to 4 weeks. The baby canines, or fangs, follow at 3 to 4 weeks, and premolars at 4 to 6 weeks. Adult teeth start to replace them at about 3 to 4 months, and the full adult set of 30 teeth is usually in by 6 to 7 months. Adult teeth look larger and whiter than the thin, needle-like baby teeth.
Care notes by stage
Under 4 weeks: bottle feeding
Feed kitten milk replacer from a kitten bottle every 2 to 4 hours, including at night for the youngest. Never use cow’s milk. Keep the kitten warm, and after each feed gently rub the belly and bottom with a warm, damp cloth to help it pee and poop. A kitten under 4 weeks old without its mother needs a vet or rescue today.
4–8 weeks: weaning
Offer wet kitten food mixed with milk replacer into a soft gruel, then thicken it over a couple of weeks. Put out a shallow litter box with unscented, non-clumping litter. Handle the kitten gently every day so it grows up relaxed with people.
6–8 weeks: first vet visit and vaccines
Most kittens have a first checkup, deworming and their first vaccines at 6 to 8 weeks, with boosters every 3 to 4 weeks until at least 16 weeks. See our kitten vaccine schedule.
2–6 months: growing up
Feed a complete kitten food several times a day. Ask your vet about the right time to spay or neuter, often around 4 to 5 months, and keep up with parasite prevention.
How can I tell how old my kitten is?
Weight is the quickest guide: a healthy kitten weighs about 1 lb per month of age up to 5 or 6 months. Teeth, eyes, ears and walking narrow it down, and a vet can give the most accurate estimate.
How much should a kitten weigh by age?
Kittens are born at about 3 to 4 oz (90 to 110 g) and gain roughly 3.5 oz (100 g) a week. That puts them near 1 lb at 4 weeks, 2 lb at 8 weeks and 3 lb at 12 weeks.
When do kittens get their teeth?
Baby incisors come in at 2 to 4 weeks, baby canines at 3 to 4 weeks and premolars at 4 to 6 weeks. Adult teeth start pushing through at about 3 to 4 months and are usually all in by 6 to 7 months.
When can a kitten leave its mother?
Kittens should stay with their mother until at least 8 weeks, and many shelters wait until 10 to 12 weeks. A kitten under 4 weeks old without its mother needs bottle feeding and help from a vet or rescue.
This is a rough estimate for healthy kittens and general information only. It doesn’t replace a vet exam, which gives the best age estimate. Source: Cornell Feline Health Center; Merck Veterinary Manual; AAFP.
