What is the ideal weight for a medium cat? There is no single number, because medium cats range from a 3 kg Siamese to an 8 kg British Shorthair — but there is a single method that works for all of them: the breed's typical weight range, checked against body condition. A medium cat is one in the 3 to 6 kg size class, and this guide is the medium cat ideal weight calculator in words: the weight chart by breed, how to judge body condition by feel and by sight, how to weigh a medium cat at home, and how to help a medium cat lose weight — or gain it — safely.
Weight matters more for medium cats than most owners realise, because every extra half kilogram is a large share of a medium cat's body weight. A medium cat carrying 1 kg too much is carrying a fifth of its body weight in extra fat — and that load shows up in stiffness, slower movement, diabetes risk, and a shorter life. The good news is that weight is the one health factor owners control almost completely: measured food, daily play, and a monthly weigh-in are enough, and the chart below tells you what number to aim for. The figures are ranges from published breed standards, not single targets — aim for the range, then use body condition to find your cat's place inside it.
What is a medium cat's ideal weight?
A medium cat's ideal weight is the weight at which the cat is lean, muscular, and moving freely — ribs easily felt under a thin layer of fat, a visible waist from above, and a tummy tuck from the side. For most medium breeds that weight falls inside the breed's typical range in the chart below, but the range is wide on purpose: a Siamese at 3 kg and a Siamese at 5 kg can both be at their ideal weight, because males are heavier than females and builds differ. What matters is not the exact number on the scales but the shape of the cat at that number.
That is why vets use a body condition score rather than a single weight. The common scale runs from 1 to 9: 1 is emaciated, 4 to 5 is ideal, and 9 is severely obese. An ideal medium cat scores 4 or 5 — ribs felt without pressing hard, waist visible from above, tummy tucked from the side, and no fat pads over the hips. A cat that scores 6 or 7 is overweight; 8 or 9 is obese and needs a vet-supervised plan. Learn the feel of your cat at its ideal weight, and you can judge it every week without scales. The cat ideal weight calculator gives a starting range for any breed and size.
Medium cat ideal weight chart by breed
Use this chart to find your breed's typical adult weight range. The ranges come from published breed standards, and the lifespan column is included because weight and lifespan are linked: medium cats typically live 11 to 20 years depending on breed, and a lean medium cat tends to live longer inside that range than an overweight one.
| Breed | Typical adult weight | Typical lifespan |
|---|---|---|
| Persian | 3–6 kg | 12–17 years |
| Siamese | 3–5 kg | 12–15 years |
| British Shorthair | 4–8 kg | 12–17 years |
| Bengal | 4–7 kg | 12–16 years |
| Sphynx | 3–5 kg | 13–15 years |
| Scottish Fold | 3–6 kg | 11–14 years |
| Abyssinian | 3–5 kg | 12–15 years |
| Birman | 3–6 kg | 12–16 years |
| Russian Blue | 3–5 kg | 15–20 years |
| American Shorthair | 3–7 kg | 15–17 years |
| Exotic Shorthair | 4–7 kg | 12–15 years |
| Himalayan | 3–5 kg | 9–15 years |
| Manx | 3–5 kg | 12–14 years |
| Burmese | 3–5 kg | 12–16 years |
| Tonkinese | 3–5 kg | 10–15 years |
| Egyptian Mau | 3–5 kg | 12–15 years |
| Turkish Angora | 3–5 kg | 12–18 years |
| Balinese | 3–5 kg | 12–20 years |
| Chartreux | 3–7 kg | 12–15 years |
| Bombay | 3–5 kg | 12–16 years |
A few things to notice in the chart. First, the ranges are wide: a British Shorthair typically weighs 4 to 8 kg, double from the light end to the heavy end, because males are much heavier than females and the breed is heavily built. A Persian typically weighs 3 to 6 kg, and a Bengal 4 to 7 kg. Second, lifespans vary far more between breeds than between sizes: a Russian Blue typically lives 15 to 20 years and a Balinese 12 to 20 years, while a Himalayan typically lives 9 to 15 years and a Scottish Fold 11 to 14 years — all medium cats. Third, for medium breeds without a published breed-standard range, the typical range for a medium cat is 3 to 6 kg, which is an estimate, not a breed-specific measurement. If your breed is not in the chart, use 3 to 6 kg as a starting point and let body condition and your vet set the real target.
How to tell if your medium cat is overweight
Start with your hands, not the scales. Stand your cat up and run your hands along its ribs: you should feel each rib easily under a thin layer of fat, without pressing hard. If you have to press to find the ribs, the cat is overweight; if you cannot feel them at all, the cat is obese. Then look from above: there should be a visible waist behind the ribs, narrower than the chest. Then look from the side: the tummy should tuck up behind the ribs, not hang in a straight line or sag. A medium cat that fails any of these checks is carrying too much weight, even if the number on the scales still falls inside the breed's range — because the range is wide and your cat may belong at the light end of it.
Other signs are easier to miss. A cat that plays less, sleeps more, grooms less, or struggles to jump onto a favourite perch may be overweight rather than simply ageing — and overweight cats are prone to diabetes and joint problems, so extra weight and ill health feed each other. Weigh the cat monthly and write the number down: a slow gain of 100 g a month is 1.2 kg in a year, which is a quarter of a 5 kg cat's body weight, and it is invisible day to day. If you are unsure, ask your vet to score body condition at the next visit and to set a target weight — that target, not the breed chart, is the number to work towards.
How to weigh a medium cat
The easiest way to weigh a medium cat is on kitchen scales for a 3 to 5 kg cat: put a basket or a box on the scales, zero them, put the cat in, and read the number. For a heavier medium cat, use bathroom scales and the hold-and-subtract method: weigh yourself, then weigh yourself holding the cat, and subtract. Weigh at the same time of day, on the same scales, once a month, and write the number down with the date — a record makes slow change visible.
Weighing is only useful if it leads to action. If the number is rising month by month, cut food by about 10% and re-weigh in a month. If it is falling without a planned diet, mention it to your vet — unplanned weight loss in a medium cat can be an early sign of illness, especially kidney or thyroid disease, and it deserves a check rather than a celebration. The cat food calculator works out daily calories for any weight, so once you know the target weight you can work out the food to match it.
How to help a medium cat lose weight safely
The safest way to help a medium cat lose weight is slow and boring: measure the food, cut it by about 10%, keep treats under 10% of daily calories, and play every day. A 5 kg medium cat that needs about 280 calories a day should lose weight on about 250 — a small cut, not a crash diet — and the weight should come off over weeks and months, not days. Weigh the food with kitchen scales, not a scoop or a handful, and weigh the cat monthly: if the number is not moving after a month, cut another 10% and check again. Never put a cat on a crash diet or starve it to lose weight quickly — rapid weight loss in cats can cause fatty liver disease, a serious and sometimes fatal condition, and a cat that stops eating entirely is an emergency, not a diet success.
Play should rise gently, not suddenly. A medium cat that is overweight and unfit should start with short, regular play sessions — five to ten minutes, two or three times a day — and build up over weeks, with puzzle feeders that make the cat work for its food. Active breeds such as Bengals and Abyssinians need more play than calm ones such as Persians, but every medium cat needs daily play. And involve the whole household: a weight-loss plan fails when one person measures food carefully and another hands out treats. Agree the daily ration, agree the treat budget, and keep a note on the fridge so everyone feeds the same amount. The medium cat food guide gives the calorie tables by weight that make the plan practical.
How to help an underweight medium cat gain weight
An underweight medium cat — ribs, spine, and hip bones visible, no fat cover, a score of 1 to 3 — needs a vet check before extra food. Weight loss or failure to gain weight in a medium cat can be caused by parasites, dental pain, thyroid or kidney problems, or a food that does not suit the cat, and feeding more of the same food will not fix any of those. Once the vet has ruled out illness, the usual advice is to increase food gradually — about 10% more, in an extra meal rather than a bigger one, so the cat's digestion copes — and to use a calorie-dense, complete and balanced food suited to the cat's life stage. Weigh weekly while the cat gains, and stop increasing once the ribs are felt under a thin layer of fat rather than seen.
Do not try to fatten a medium kitten, and never overfeed a kitten to make it grow faster: excess weight in kittenhood sets up weight problems for life, and the kitten should stay lean enough that you can feel its ribs easily. If your medium cat is a senior that has lost weight, mention it to your vet promptly — weight loss in an older cat is often the first sign of kidney or thyroid disease, and early help works better than late help. The cat food calculator works out the calories for the target weight once your vet has set it.
What affects a medium cat's ideal weight
Age is the biggest factor after breed. Kittens grow fast and their weight changes weekly; adults should hold steady; seniors often lose muscle and may need fewer calories but the same good protein, and some seniors gain weight because they move less while food stays the same. Neutering typically cuts calorie needs by about 10 to 20%, so expect to cut food after the operation and watch the waistline for the next few months. Activity matters too: a Bengal that plays hard all day needs more food than a Persian that sleeps, and a cat that becomes indoor-only needs less than one that used to roam.
Sex and build matter as well — males are usually heavier than females, and some medium breeds are naturally fine-boned while others are cobby — which is another reason the chart gives ranges rather than single numbers. Health conditions change the target entirely: a cat with diabetes or joint disease benefits from being at the light end of its range, while a cat recovering from illness may need to be heavier for a while. In every case the target is a conversation with your vet, not a number from a chart. Use the chart to know roughly where your cat should be, use body condition to judge where it actually is, and use your vet to set the plan that closes the gap. The Persian food guide and the Bengal food guide show how the same method applies breed by breed.
For related reading, see the cat ideal weight calculator, the medium cat food guide, the medium cat age guide, the Persian food guide, the Bengal food guide, the cat breeds hub.
Frequently asked questions
What is the ideal weight for a Persian?
A Persian typically weighs 3 to 6 kg as an adult. Within that range, the ideal weight is the one at which the ribs are easily felt under a thin layer of fat, a waist is visible from above, and the tummy tucks up from the side. Most Persians do best in the middle of the range, because they are cobby cats — heavy-boned for their size — and a Persian at the top of the range is often overweight rather than simply large.
How do I know if my medium cat is overweight?
Feel the ribs: you should feel them easily without pressing hard. Look from above for a visible waist behind the ribs, and from the side for a tummy tuck. If you have to press to find the ribs, or there is no waist, the cat is overweight. Weigh the cat monthly and ask your vet to score body condition at the next visit.
How do I weigh a 6 kg cat at home?
Use bathroom scales and the hold-and-subtract method: weigh yourself, then weigh yourself holding the cat, and subtract. For a 3 to 5 kg cat, kitchen scales with a basket are more accurate. Weigh at the same time of day, once a month, and write the number down — a record makes slow change visible.
How fast should a medium cat lose weight?
Slowly, over weeks and months, with a small cut of about 10% of daily food and a monthly weigh-in. Never starve a cat or crash-diet it: rapid weight loss in cats can cause fatty liver disease, a serious condition, and a cat that stops eating entirely is an emergency. If the weight is not moving after a month on a 10% cut, cut another 10% and check again — and ask your vet to set the target and the pace.
Do medium cats need a different food to stay at a healthy weight?
Not necessarily a different brand, but the right amount of a complete and balanced food suited to the cat's life stage, measured every day. What matters most is the amount: weigh the food with kitchen scales, keep treats under 10% of daily calories, and adjust by the monthly weigh-in. Cats are obligate carnivores, so the food must contain animal protein and taurine.
When should I ask my vet about my medium cat's weight?
At the next routine visit if the cat is overweight or underweight, and promptly if weight is changing without a planned diet — especially weight loss in a senior cat, which can be an early sign of kidney or thyroid disease. Your vet can score body condition, set a target weight, and check for the health problems that cause weight change.
Results on this page are estimates for general information only and are not veterinary advice. If your pet is ill, underweight, overweight, pregnant, or has a health condition, consult your veterinarian before changing diet or care.