How Heavy Should My Cat Be? Use the BCS Scale to Measure a Cat’s Health

On average, a healthy domestic cat will weigh around 4.5kg—although, that isn’t a hard and fast rule. How heavy your cat should be will vary, depending on your cat’s breed, body frame, and whether they’re indoor or outdoor cats. A normal, healthy weight for a button-sized Singapura, for instance, will be much lower than the expected weight of a mammoth Maine Coon (up to 11kgs!)

The best way to determine your cat’s target weight is by talking to your vet. Your vet can help you pinpoint a healthy weight for your cat and offer guidance on reaching it. Maintaining the right weight is essential to your cat’s long-term health as overweight and underweight cats face an increased risk of heart problems and a shortened life span.

Feeding your cat age-appropriate food with sufficient protein is the recommended way to keep their weight on track. Meals should be measured, but the exact amount will depend on your cat’s breed, energy levels, and individual calorie needs.

Cat Weight Chart: What is Average, Under, and Overweight?

For an objective picture of your cat’s size, your vet can assign them a body condition score—a metric that looks at more than just the numbers on the scale.

Dr Gary Richter, Rover’s resident vet on The Dog People Panel, explains: “A numerical system called the body condition score (BCS) is a simple way of tracking whether your pet is at an ideal weight, too fat, or too thin. Veterinarians use this tool to assess the body weight and overall condition of a dog or cat based on fat deposits and how prominent the animal’s bones are.”

	Underweight	Healthy	Overweight
Tummy	Ribs are visible from above	Visible waistline, almost like an hourglass	No waistline and more round in nature
Ribs	Bony and protruding	Not visible but can be felt	Unable to feel their ribs
Energy levels	Low	Normal	Low

To unpack the BCS system, we spoke with Dr Danielle (Elly) Page BVSc, a North Carolina-based vet and passionate advocate for healthy pet weight.

If you’re new to this scale, Dr Page suggests getting some pointers from your vet, first. “I would definitely recommend getting your veterinarian to teach you how to work out if your cat is the correct weight,” she says. “Once you know what you’re looking for, it’s pretty simple to determine if your cat is a healthy weight.”

How to use the body condition score on your cat:

1. First, take a visual look. “A cat that is a healthy weight should have a tummy tuck and an hourglass look when viewing from above,” says Dr Page. For healthy cats, ribs should not be visible.
2. Then, do a hands-on check. “If you run your hands along their sides, you should be able to feel the ribs under a thin layer of fat,” Dr Page tells us. She continues: “If you can’t feel their ribs, they are likely overweight. If their ribs are very bony, they may be underweight.”
3. Lastly, address any changes in behaviour. A cat who’s too heavy or too thin may experience dips in energy. Pay attention to your cat’s activity levels, and inform your vet of any changes. “Overweight cats often sleep more and find it difficult to jump up onto high surfaces,” says Dr Page, adding the following words of caution: “Both of these signs can also be due to problems such as arthritis, so it’s best to get your vet to check out your cat.”

How Does My Cat’s Weight Affect Their Health?

Your cat’s weight isn’t just a matter of aesthetics—it can affect their quality of life, according to the Cornell College of Veterinary Medicine in the USA. For starters, carrying around extra weight will deplete your cat’s energy level. It also complicates their ability to perform routine kitty activities, like jumping on the counter or bed. Too much weight will put stress on your cat’s joints, and it can negatively affect your cat’s heart health.

Underweight cats face health risks as well, including nutritional deficits and weakened immune systems. Skipping meals is not a healthy habit for cats—and because it usually signifies an underlying issue, food avoidance should always be addressed by your vet.

Is My Cat Overweight? Characteristics and Symptoms

“Obesity is an ever-growing issue in our pets—and cats are the worst affected with estimates of over 50% of our cats in the USA being overweight or obese,” says Dr Page.

The two main causes of feline weight gain are too much food and too little exercise. Many of us are free-feeding our cats, who (like humans) aren’t always the best at recognising when enough is enough. Plus, most indoor cats (again, like humans) aren’t getting enough exercise.

For folks asking themselves “is my cat overweight?” or “are they be obese?” Dr Page breaks it down for us.

“An overweight cat is 10-19% above its ideal body weight,” she says. So if your cat is 5kg, and should be 4.5kg, they would be considered overweight. Meanwhile, Dr Page points out: “An obese cat is 20% or more above its ideal body weight.” So, if your cat is more than 5.9kg, and should be 4.5kg, they’ll be considered clinically obese.

Physical signs of cat obesity:

• rounded body
• fat pad hanging on their underside
• you can’t feel your cat’s ribs or backbone

Symptoms and disorders caused by obesity:

• diabetes mellitus
• hypertension
• some types of cancer
• surgical and anaesthetic complications
• non-allergic skin conditions
• feline lower urinary disease
• weakened immune system
• hepatic lipidosis (fatty liver disease)

Medical causes of cat obesity:

• heart disease
• lung disease
• arthritis

Is My Cat Underweight? Characteristics and Symptoms

Sometimes, a diminished appetite is tied to psychological stress. Cats may lose interest in food after a move or when a new pet is introduced to the home. Picky cats have also been known to refuse food if they don’t find it palatable.

Whatever the cause of anorexia in cats—a sustained loss of appetite—the condition always warrants medical attention, Dr Page tells us.

“I would rarely see a cat (I have actually never seen one) that is underweight or refusing to eat for no reason at all. Every cat I have seen that is in this camp is due to an underlying issue, such as kidney disease or dental disease.”

It’s no reason to panic, but a call to your vet is definitely in order. “I would advise you to get your cat checked out by your vet, as many reasons for refusing to eat can be life-threatening if not treated.”

Physical signs of feline anorexia:

• extreme tummy tuck
• visible ribs
• little to no padding on the tailbone

Symptoms and disorders associated with feline anorexia:

• hepatic lipidosis (fatty liver disease) can develop during even short periods of not eating
• weakened immune system
• muscle weakness
• risk of sepsis
• difficulty healing
• digestive issues

Medical causes of feline anorexia:

• upper respiratory tract disease
• dental problems
• pancreatitis
• liver disease
• gastrointestinal (GI) problems
• cardiac disease
• anaemia
• neoplasia

What Should I Do If My Cat Is Overweight?

The first rule of feline weight loss: takes things slowly. A drastic diet that causes your cat to lose weight too quickly will do more harm than good. Under no circumstances, should you ever starve your cat. Rapid weight loss may even lead to fatty liver disease, which can be fatal if left untreated.

So, what’s a safe cat weight loss rate? According to vets at Tufts University, a modest 0.5% to 2% loss of body weight per week is a good goal. With your vet’s guidance, you can come up with a plan to manage your kitty’s extra weight. Here are several steps to get you started.

1. Choose a diet cat food. Instead of limiting your cat’s food intake (which can land him with nutritional deficiencies), talk to your vet about switching to a low-fat cat food for weight loss. The best cat food for overweight cats will be rich in lean animal protein (at least 30%), low in calories, and contain digestible carbohydrates and fibre.
2. Schedule and measure feeding times. Free-feeding is at the root of many feline weight issues, Dr Page points out. “Many overweight cats live for the times you fill their food bowl and will eat all the food in one sitting.” The solution? Measured and scheduled meals. “For overweight cats, it’s important to measure out their food,” says Dr Page. “I highly recommend weighing it on your kitchen scales, and splitting it into three meals: morning, afternoon (when you get back from work), and just before you go to bed.”
3. Limit treats. No need to cut out treats entirely, but keep them to less than 10% of your cat’s caloric intake. For diet-friendly snacks, consider a healthy cat treat that’s high in protein and low in calories.
4. Encourage exercise with toys. One way to get your reluctant couch potato up and moving is with an interactive cat toy. Most cats enjoy toys that mimic prey. Or you can go with a classic, and promote exercise with a cat laser toy.
5. Use a puzzle feeder. Not only are puzzle feeders mentally enriching, but studies also show they slow down voracious eaters and can help cats lose weight.
6. Try a cat tree. Cats are all about that vertical space, and a cat tree gives them somewhere to jump, climb, and stretch out their limbs.
7. Give a cat harness a whirl. No, not every cat will tolerate a harness. But for willing kitties, a cat harness opens up a whole world to explore. Or maybe just the backyard. Either way, it’s a novel way to clock in some additional steps with your cat.

What Should I Do If My Cat Is Underweight?

First, underweight cats should be evaluated by a vet to rule out any potential medical causes for their weight loss. From there, a pet nutritionist or vet can help you identify any diet or lifestyle changes that need to be made. We just have one watchout: while tempting, it’s important to resist the urge to overload your thin cat with extra treats and food.

Here are eight ways to manage anorexia in cats:

1. Switch to a cat food designed for weight gain. Ask your vet if you should swap your cat’s regular kibble with a high-calorie cat food for weight gain. Ideally, the best cat food for weight gain will be made with 30% protein and 20% fat.
2. Try a new flavour. Cats can be fussy when it comes to food. If yours is staging a hunger strike, try a different brand or flavour of food to see if it piques their interest.
3. Feed them more meals. Try offering your cat smaller, more frequent meals throughout the day (say three to four, instead of his usual two).
4. Switch to wet food. Canned food may help your underweight cat beef up, reports Dr Page. “Some cats do better switching to wet food exclusively. Wet foods typically (but not always) have higher protein and more volume than dry.” Plus, cats usually find wet food more palatable than dry food.
5. Warm up your cat’s food. This simple step makes food more enticing to your cat’s sensitive sniffer.
6. Boost palatability. To make your cat’s meal more appealing, try adding nutritious toppers or a splash of chicken broth to soften food and add flavour.
7. Reduce environmental stressors. For stress-related anorexia, try to create a calm and quiet space for your cat to enjoy his food in peace.
8. Keep food fresh. No one wants to nosh on stale food. For optimal freshness, store cat food in an airtight container and keep it in a cool, dry spot.

Is My Cat’s Primordial Pouch a Sign of Excess Fat?

If your cat is swinging a sizable paunch around his midsection, it isn’t necessarily fat. It could just be his primordial pouch, which is 100% normal and healthy. All cats (male and female) sport this layer of fat, skin, and fur on their underside, although some are more visibly pronounced than others.

There are a few theories behind the pouch’s purpose. It’s possible cats developed them as an added layer of protection around their internal organs. Or, perhaps, they served as extra space to store food in-between hunts.

Because obesity carries with it so many risks, cat owners should know the difference between a harmless primordial pouch and an unsafe layer of fat. Dr Page offers this distinction: “The pouch will be loose and have minimal fat underneath it. If you flatten it against the cat’s body, it will still have a tuck. Whereas that will not be the case with an overweight paunch.”

Takeaway: Measure Your Cat’s Health Individually, Not By Internet Numbers

Here’s the bottom line: what’s healthy for one cat can be totally different from the next. Determining your own cat’s healthy weight will involve a number of considerations, including their breed, age, and medical history.

When your cat needs a little help in the weight department, your best ally is your veterinarian or pet nutritionist. Always speak with a professional before making changes to your cat’s diet. They can help you devise the safest weight management plan for your cat.