Kitten Weight Chart
This free kitten weight chart shows how much a kitten should weigh by age — by day, week and month — in grams, kg and lb, and turns the chart into a working tool: check if your kitten is on track, track daily weight gain, and predict adult size by breed.
How to Use This Kitten Weight Chart
To weigh a kitten accurately, use a digital kitchen or postal scale for young kittens (they’re too light for a bathroom scale) and weigh at the same time each day. Record the number, then come back and use the Growth Tracker to see the daily gain.
How Much Should a Kitten Weigh by Age?
Here is the full kitten weight chart by age, showing the typical healthy weight in grams, kilograms and pounds. These are averages for a mixed-breed (domestic) kitten; large breeds run heavier and fine-boned breeds run lighter.
| Age | Grams | Kilograms | Pounds |
|---|---|---|---|
| Newborn | 85–115 g | 0.09–0.12 kg | 3–4 oz |
| 1 week | 150–250 g | 0.15–0.25 kg | 0.3–0.6 lb |
| 2 weeks | 250–350 g | 0.25–0.35 kg | 0.6–0.8 lb |
| 3 weeks | 350–450 g | 0.35–0.45 kg | 0.8–1.0 lb |
| 4 weeks (1 month) | 400–550 g | 0.4–0.55 kg | ~1 lb |
| 6 weeks | 600–800 g | 0.6–0.8 kg | 1.3–1.8 lb |
| 8 weeks (2 months) | 800–1100 g | 0.8–1.1 kg | ~2 lb |
| 12 weeks (3 months) | 1200–1600 g | 1.2–1.6 kg | ~3 lb |
| 16 weeks (4 months) | 1600–2100 g | 1.6–2.1 kg | ~4 lb |
| 20 weeks (5 months) | 2000–2700 g | 2.0–2.7 kg | 4.5–6 lb |
| 24 weeks (6 months) | 2500–3200 g | 2.5–3.2 kg | 5.5–7 lb |
| 8 months | 2900–3900 g | 2.9–3.9 kg | 6.5–8.5 lb |
| 12 months (adult) | 3200–4500 g | 3.2–4.5 kg | 7–10 lb |
How Old Is a 1 kg Kitten?
A kitten weighing about 1 kg (roughly 2.2 lb) is typically around 8 weeks (2 months) old, since the average 2-month-old sits near 0.8–1.1 kg. Weight is only a rough guide to age, though. A fast-growing or large-breed kitten can hit 1 kg closer to 6–7 weeks, while a small or fine-boned kitten may not reach it until 9–10 weeks. To estimate age more reliably, vets look at teeth, eyes and overall development as well as weight — use the Weight-for-Age Chart tab above to see the age a given weight points to.
How Heavy Is a 4-Month-Old Kitten?
A 4-month-old (16-week) kitten usually weighs about 1.6 to 2.1 kg (roughly 4 lb) — a neat fit for the one-pound-per-month rule. By four months a kitten has done most of its fastest growing and is about half of its adult weight, which is why the four-month mark is the best time to predict adult size. Large breeds such as the Maine Coon and Ragdoll are often heavier, sometimes 2.5–3 kg (6–7 lb) by this age, while Siamese and Oriental kittens are usually lighter. If your four-month-old is well outside this range, check its body condition and ask your vet.
How Do I Know My Kitten’s Weight?
The most accurate way is a digital scale. For a young kitten, use a kitchen or postal scale that reads in grams — place it in a small bowl or box and subtract the container’s weight (tare it if you can). For an older kitten, weigh yourself holding it on a bathroom scale, then weigh yourself alone and subtract. Weigh at the same time of day on the same scale for consistency. Newborns and very young kittens should be weighed daily; from a few weeks old, every few days to weekly is enough. Log each weight and watch the trend — a steady climb matters far more than any single reading.
How to Predict How Big a Kitten Will Be
The most popular shortcut is to double your kitten’s weight at 16 weeks (4 months) for a rough adult weight. A more gradual method, used by the Adult Size Predictor above, is that a kitten reaches a known fraction of its adult weight at each age — about 50% at 4 months, 70% at 6 months and 95% by a year — so you can divide the current weight by that fraction. Other clues help: large paws and long legs, the size of the parents (if known), and the breed. Keep in mind that large breeds keep growing well past a year, often to three or four years old, so an early estimate can undershoot a Maine Coon or Ragdoll.
| Breed | Typical adult weight | Size class |
|---|---|---|
| Siamese / Oriental | 2.7–4.5 kg (6–10 lb) | Small, fine-boned |
| Domestic shorthair | 3.6–5.4 kg (8–12 lb) | Average |
| Persian | 3.2–5.5 kg (7–12 lb) | Average |
| Bengal | 4.0–6.8 kg (9–15 lb) | Average–large |
| Ragdoll | 4.5–7.0 kg (10–15 lb) | Large |
| British Shorthair | 4.0–7.0 kg (9–15 lb) | Large |
| Maine Coon | 5.9–8.2 kg (13–18 lb) | Large |
Why Body Condition Beats the Chart
A weight chart is a starting point, not a diagnosis. Two healthy kittens of the same age can differ by a lot because of breed, frame and sex (males usually finish heavier). What vets actually rely on is the body condition score: you should be able to feel the ribs easily with a thin fat covering, see a slight waist from above, and feel a small belly tuck. If a kitten is within the chart band and has good body condition, it’s on track. If it’s well outside the band, losing weight, or the condition looks wrong, that’s the signal to call your vet — not the chart number alone.
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