Kitten Growth and Weight Chart by Age

Name: Kitten Growth and Weight Chart by Age
Creator: Dr. Zubair Khalid

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-10-02

A kitten weight chart by age gives you a simple way to check that your kitten is growing at a healthy pace. Most kittens gain steadily every week, and the number on the scale tells you more about their health than how they look. Weighing your kitten at home and tracking the trend is one of the most useful things you can do in the first months.

This article is educational and is not a substitute for veterinary diagnosis or treatment.

Quick Answer

Healthy kittens gain weight steadily every week from birth through about 6 months, then growth slows.
A common rule of thumb is that a kitten weighs roughly 1 pound per month of age, so a 3-month-old kitten is often near 3 pounds.
Weigh your kitten on a kitchen scale in grams or ounces, at the same time of day, and write down each number.
Losing weight, staying flat for more than a few days, or falling far below the expected range needs a veterinary visit.
Your veterinarian's exam and body condition score matter more than any single number on a chart.

How to Use a Kitten Weight Chart by Age

Weigh at home the right way

Use a digital kitchen scale that reads in grams or ounces. A kitten is too small for a bathroom scale. Weigh your kitten at the same time each day, ideally before the first meal, and record the number in a notebook or phone app. If your kitten will not sit still, weigh yourself holding the kitten, then weigh yourself alone, and subtract.

Track the trend, not one number

A single weight is a snapshot. The pattern over days and weeks is what tells you whether growth is on track. Kittens should gain something almost every day in the first weeks of life. A kitten who gains a little less on one day is usually fine. A kitten who has not gained for several days in a row is a concern.

Compare with the chart, then check body condition

Charts give ranges, not exact targets. Two healthy kittens the same age can differ by several ounces. Run your hands along your kitten's ribs. You should feel the ribs easily under a thin layer of fat, without seeing them sharply. A rounded belly is normal in young kittens, but a bony spine or hips suggest the kitten is too thin.

Adjust feeding based on the trend

If your kitten is gaining well, keep doing what you are doing. If growth is slow, your veterinarian can help you decide whether to increase the amount, change the food, or check for a health problem. Feeding amounts differ by food, so follow the label as a starting point and let your veterinarian fine-tune it.

Kitten Growth Chart: What to Expect Week by Week

This table shows typical patterns. It is a guide, not a rule. Your veterinarian can tell you whether your kitten's specific numbers are healthy.

Age	Typical weight range	What is happening
Birth	3 to 3.5 oz (85 to 100 g)	Eyes and ears closed, nursing every 2 to 3 hours
1 week	4 to 7 oz (110 to 200 g)	Eyes begin to open, weight should rise daily
2 weeks	7 to 11 oz (200 to 300 g)	Ears open, starting to stand and wobble
3 weeks	10 to 14 oz (280 to 400 g)	First teeth appear, beginning to explore
4 weeks	13 oz to 1 lb 2 oz (370 to 500 g)	Walking well, may start sampling soft food
5 to 6 weeks	1 to 1.5 lb (450 to 700 g)	Weaning begins, play and social skills grow
7 to 8 weeks	1.5 to 2 lb (700 to 900 g)	Most kittens go to new homes around this age
2 months	About 2 lb (900 g)	Steady gain, vaccinations often start
3 months	About 3 lb (1.4 kg)	Active, curious, eating solid food
4 months	About 4 lb (1.8 kg)	Rapid growth continues
5 months	About 5 lb (2.3 kg)	Growth starts to slow
6 months	5 to 7 lb (2.3 to 3.2 kg)	Near adult size for many cats
9 to 12 months	7 to 12 lb (3.2 to 5.4 kg)	Adult weight reached, varies a lot by breed

The "1 pound per month" pattern is a useful shortcut for the first 6 months. After that, growth slows and adult size depends on breed, sex, and genetics. Large breeds and most male cats end up heavier than small breeds and most females.

Kitten Age Chart: Matching Age to Milestones

An age chart helps you connect what you see to what your kitten should be doing. If you do not know your kitten's exact birthday, your veterinarian can estimate age from teeth, eyes, and weight.

0 to 2 weeks: Eyes and ears closed or just opening. Fully dependent on the mother or on bottle feeding.
2 to 4 weeks: Eyes open, ears open, starting to walk. First teeth come in around 3 weeks.
4 to 8 weeks: Playing, learning to eat soft food, litter box skills developing. This is a key socialization window.
8 weeks to 6 months: Rapid growth, vaccination series, and planning for spay or neuter. If you are wondering about timing for that surgery, see Cat Neuter Age.
6 to 12 months: Growth slows, adult body shape appears, and permanent teeth come in.

Microchipping is often done around the same time as other routine procedures. For timing details, see Age To Microchip Kitten.

Kitten Size Chart: Why Breeds Differ

A kitten size chart based on mixed-breed averages will not fit every cat. Breed matters a lot. A Maine Coon kitten may weigh far more than a domestic shorthair at the same age and still be perfectly healthy. Body frame, sex, and genetics all shift the numbers.

Use the chart as a starting range, then let your veterinarian plot your kitten's own growth curve. A kitten who is consistently at the low end of the range but gaining steadily is usually fine. A kitten who drops off their own curve is the one to worry about.

Signs That Something Is Wrong

Watch for these warning signs and act on them.

Weight loss at any age. Any drop in weight in a kitten deserves a call to your veterinarian.
No gain for 2 to 3 days. Especially in kittens under 8 weeks, this can signal illness or feeding problems.
Falling far below the chart range. A kitten well under the expected weight for their age needs an exam.
Lethargy, weakness, or not wanting to eat. These are urgent signs, particularly in very young kittens.
Diarrhea, vomiting, or a bloated belly. Young kittens dehydrate quickly.
Difficulty breathing, crying constantly, or feeling cold to the touch. Seek emergency care right away.

Weight loss in adult cats has its own set of causes. If your cat is older and losing weight, see How to Tell If Your Cat's Weight Loss Is Normal Aging or a Health Problem. For the opposite problem, unexplained weight gain has its own list of causes, covered in Cat Weight Gain Causes.

Common Mistakes Owners Make

Relying on looks alone

A fluffy kitten can look plump while being underweight. A short-haired kitten can look thin while carrying normal fat. Hands-on body condition and a scale give you better information than appearance.

Weighing at random times

Weight changes through the day based on meals, water, and litter box use. Weigh at the same time each day for a fair comparison.

Using an adult scale

A bathroom scale cannot detect the small changes that matter in a young kitten. Use a kitchen scale that reads in small increments.

Comparing your kitten to a friend's kitten

Litter size, breed, and genetics all affect growth. A single kitten from a small litter often grows faster than a kitten from a large litter. Compare your kitten to their own past weights first.

Waiting too long when growth stalls

Kittens have little reserve. A few days of poor growth can turn into a serious problem fast. Call your veterinarian early.

Feeding adult food too soon

Kittens have different nutritional needs than adults. Feed a diet labeled for growth or all life stages until your veterinarian says otherwise.

Supplies and Setup That Support Healthy Growth

Digital kitchen scale. Reads in grams or ounces and lets you track small changes.
Kitten-formula food. Look for a label stating the food meets growth or all life stages.
Shallow food and water dishes. Easy for small kittens to reach without tipping.
A warm, draft-free sleeping area. Young kittens cannot regulate body temperature well.
A notebook or app for weights. Write down the date, time, and number every time.
A calendar for vet visits. Vaccines, deworming, and checkups follow a schedule in the first year.

Nutrition needs change as cats age. Senior cats have their own set of nutritional considerations, and research continues to examine how diet affects older cats [1]. Obesity is another long-term concern, and body condition scoring is the tool veterinarians use to catch it early [2].

Limitations and When to Contact a Veterinarian

Charts cannot replace an exam. Every kitten is an individual, and only your veterinarian can assess your specific kitten's health. Use these timing guidelines.

Call your veterinarian the same day if:

Your kitten has lost weight or has not gained for 2 to 3 days.
Your kitten is eating less, vomiting, or has diarrhea.
Your kitten seems weak, quiet, or less interested in play.

Go to an emergency clinic now if:

Your kitten is struggling to breathe, is limp, or feels cold.
Your kitten cannot stand or is having seizures.
Your kitten has repeated vomiting or severe diarrhea with no interest in eating.

Schedule a routine visit if:

You are unsure whether your kitten's growth is on track.
You need help choosing a food or feeding amount.
Your kitten is due for vaccines, deworming, or a spay or neuter discussion.

If your kitten is not gaining weight as expected, your veterinarian will look for causes such as parasites, infections, dental problems, or feeding issues. In some cases of unintended weight loss in cats, veterinarians use prescription medications to support weight gain, and the dose is always calculated from the individual cat's weight and health status [3]. Never give any medication to a kitten without veterinary guidance.

Frequently Asked Questions

How much should my kitten weigh at 8 weeks?

Most kittens are around 1.5 to 2 pounds at 8 weeks. Mixed-breed kittens often land near this range, while large breeds may weigh more. Your veterinarian can tell you whether your kitten's specific weight fits their growth curve.

Is it normal for a kitten to lose weight?

No. Kittens should gain weight steadily, so any loss is a reason to call your veterinarian. Even a small drop in a young kitten can point to illness, parasites, or a feeding problem.

How often should I weigh my kitten?

Daily weighing is best for kittens under 8 weeks, and every few days is fine after that. Always weigh at the same time of day for a fair comparison. Keep a written record so you can spot trends.

When do kittens stop growing?

Most kittens reach near adult size by 6 to 9 months, with some filling out until about 12 months. Large breeds can keep growing past a year. Adult weight varies widely by breed and sex.

Can I use a dog growth chart for my kitten?

No. Cats and dogs grow at different rates and reach different adult sizes. Use a chart made for kittens, and ask your veterinarian to interpret it for your cat.

Do I need a special scale?

A digital kitchen scale that reads in grams or ounces works well. A bathroom scale is not sensitive enough for small kittens. If you cannot weigh your kitten at home, your veterinarian's office can do it at each visit.

What if my kitten is smaller than the chart?

A kitten who is small but gaining steadily may simply be a small cat. A kitten who is small and not gaining needs a veterinary exam. Genetics, litter size, and breed all affect size.

Should I feed my kitten as much as they want?

Many kittens do well with measured meals or free feeding of a growth diet, but the right approach depends on your kitten. Your veterinarian can help you set an amount based on weight and body condition. Overfeeding can lead to obesity later in life, which affects health and blood values in adult cats [2].

How do I know if my kitten is getting enough to eat?

Steady weight gain, good energy, and normal stool are the main signs. If your kitten cries after meals, seems hungry all the time, or is not gaining, talk to your veterinarian. Feeding amounts vary by food and by kitten.

Can a kitten catch up if they start slow?

Many kittens do catch up with good nutrition and veterinary care. The earlier a growth problem is found, the better the outcome. Bring your kitten in as soon as you notice slow growth.

References

EXPRESS: What Goes in the Bowl? Evidence-Based Nutrition for Ageing Domestic Cats. Journal of feline medicine and surgery, 2026.
Effect of obesity and overweight on serum concentrations of hepcidin and iron in cats. New Zealand veterinary journal, 2026.
Capromorelin promotes weight gain in cats with unintended weight loss: a randomized, masked, placebo-controlled clinical trial. Journal of feline medicine and surgery, 2025.