Cat Weight Chart

What should your kitten weigh at 8 weeks, 4 months or a year? Check the typical ranges, then compare your own kitten.

Check your kitten

On the light side

Typical at 12 weeks: 2.6 lb–3.5 lb (1,200–1,600 g).

Yours: 998 g

Kittens vary with breed and litter size. A kitten slightly outside the range who is eating, playing and gaining steadily is usually fine; a kitten who stops gaining is not.

How fast kittens grow

  • Birth: about 100 g (3–4 oz).
  • First two weeks: weight roughly doubles by 7–10 days.
  • To 12 weeks: about 100 g (3.5 oz) gained each week.
  • 3–6 months: roughly 1 lb per month of age.
  • 12 months: close to adult size for most domestic cats.

These patterns come from breeder and veterinary references such as International Cat Care and the Cornell Feline Health Center. For adult cats, judge by body condition rather than a single number.

Kitten weight chart by age

AgeGramsOuncesPounds
Birth85–1153.0–4.10.2–0.3
1 week150–2505.3–8.80.3–0.6
2 weeks250–3508.8–12.30.6–0.8
3 weeks350–45012.3–15.90.8–1.0
4 weeks400–55014.1–19.40.9–1.2
6 weeks600–80021.2–28.21.3–1.8
8 weeks800–1,10028.2–38.81.8–2.4
10 weeks1,000–1,40035.3–49.42.2–3.1
12 weeks1,200–1,60042.3–56.42.6–3.5
4 months1,600–2,20056.4–77.63.5–4.9
5 months2,000–2,70070.5–95.24.4–6.0
6 months2,400–3,20084.7–112.95.3–7.1
9 months3,000–4,000105.8–141.16.6–8.8
12 months3,200–4,800112.9–169.37.1–10.6

Adult cat weight chart by breed

Typical healthy adult ranges; males are usually at the upper end.

BreedHealthy adult weight
Domestic shorthair / longhair8–12 lb (3.6–5.4 kg)
Siamese6–12 lb (2.7–5.4 kg)
British Shorthair9–17 lb (4–7.7 kg)
Persian7–12 lb (3.2–5.4 kg)
Bengal8–15 lb (3.6–6.8 kg)
Ragdoll10–20 lb (4.5–9 kg)
Maine Coon10–25 lb (4.5–11.3 kg)
Sphynx6–12 lb (2.7–5.4 kg)
Abyssinian6–10 lb (2.7–4.5 kg)
Norwegian Forest Cat9–20 lb (4–9 kg)

Is my adult cat overweight?

Run your hands along your cat’s sides. You should feel the ribs under a thin layer of fat without pressing, see a waist behind the ribs from above, and find only a small belly pouch. If the ribs are hard to feel, your cat is likely overweight; our cat food calculator has a weight-loss setting.

Questions owners ask

How much should a kitten weigh?
A healthy kitten weighs about 100 g (3.5 oz) at birth, doubles that in the first week or two, and gains roughly 100 g a week until about 12 weeks. A handy rule from 3 to 6 months: about 1 lb per month of age.
What is a healthy weight for an adult cat?
Most domestic cats are healthiest at 8–12 lb (3.6–5.4 kg), but frame size matters: a Maine Coon can be lean at 18 lb. Body condition (ribs, waist, belly) is a better guide than the number; vets use a 1–9 score where 5 is ideal.
How do I weigh my kitten?
Use a digital kitchen scale in grams for kittens under a few months. For bigger cats, weigh yourself, then weigh yourself holding the cat and subtract.
When should I worry about my kitten’s weight?
Newborn kittens should gain every day. Any weight loss, no gain for 2 days in the first weeks, or a kitten much smaller than its littermates is a reason to call your vet promptly — young kittens can decline fast.
When is a cat fully grown?
Most cats reach adult size around 12 months, though they may keep filling out until 18–24 months. Large breeds like Maine Coons and Ragdolls can keep growing until 3–4 years.

Sources: International Cat Care; Cornell Feline Health Center; WSAVA Body Condition Score chart for cats; 2021 AAHA/AAFP Feline Life Stage Guidelines.

Keep going

Cat age calculatorCat years to human years, with the full age chart.Cat food calculatorCalories and a wet/dry split for your cat.Cat pregnancy calculatorKitten due date and what happens when.