How old is my kitten?
A newborn kitten weighs about 85 to 225 g with closed eyes; eyes open at 1 to 2 weeks, first wobbly steps come at about 3 weeks, adult eye colour and solid food at 4 to 5 weeks, and at 8 weeks a kitten weighs about 900 g (2 lb).
Free, no sign-up · Reviewed October 2026 · How it works
Use kitchen scales in grams if you can.
Eyes
Moving
Eating
Estimated age
4 to 6 weeks
Add a weight to narrow it down.
Kittens can usually be fully weaned from about 8 weeks, when they weigh around 2 lb (900 g), and are ready for first vaccinations from 6 to 8 weeks. Ask a vet to confirm the age at the first check.
- Under 1 week
- 85–225 g, eyes shut
- 1–2 weeks
- 225–310 g, eyes opening
- 3 weeks
- 210–410 g, first steps
- 4–5 weeks
- 225–475 g, adult eye colour
- 8 weeks
- About 900 g (2 lb), looks like a small cat
How this tool works
Each answer (eyes, movement, eating and, if you have it, weight) matches a range of ages from the Alley Cat Allies kitten development guide. The calculator shows where those ranges overlap.
Weight is the most precise guide in the first 8 weeks. After that, kittens gain roughly 450 g (1 lb) a month until about 5 months.
Very young kittens need urgent care: if your kitten is under 4 weeks old, contact a vet or rescue today.
Questions.
How can I tell how old a kitten is?
Check weight, whether the eyes are open and what colour they are, whether the ears are upright, how well the kitten walks and whether it eats solid food. Together they give a good estimate up to about 8 weeks.
What should I do if I find a kitten?
Watch from a distance for a few hours if the kitten seems healthy, as the mother is often nearby. If it's cold, injured or alone for a long time, keep it warm and call a vet or local rescue. Never give cow's milk.
When can kittens leave their mother?
Not before 8 weeks, and ideally 10 to 12 weeks, when they're weaned and have learned from their mother and littermates.
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