Healthy and Ideal Cat Weight | What’s Right for Your Cat

We love our kitties and most kitties love food and treats, so in many cat parent’s minds, treats = love. Some people are so convinced that giving a cat food is a way of showing affection that it almost seems like they’re in some kind of competition to create the heaviest cat. Other cat parents just don’t realize that their cat is overweight since fat cats have kind of become the norm. On the other side of things, an underweight cat can be a concern as well, especially if they have some recent unexplained weight loss. If your cat’s weight is in question, we’re here to help you determine what is a healthy weight and how to safely achieve it.

got a fat cat - exercise

Why is a Healthy Weight So Important in Cats?

The weight of your cat can have a significant impact on their lifestyle and lifespan. Just like humans, being overweight greatly increases their chances of contracting certain diseases like diabetes and arthritis. In cats, excess weight can also contribute to urinary issues. Heavy kitties are also less likely to be physically active which can greatly decrease their mental health and happiness as well.

Kitties that are underweight may suffer a greater risk of injury due to decreased muscle mass and lack of a protective fatty layer. They may also be less energetic.

What is Average Cat Weight?

Now, this is a question best answered by your veterinarian. There is no one-size-fits-all number that you can assign to cats in general to indicate a healthy weight. Rather, the ideal weight for your cat will depend on their frame size and breed. Weights can vary from as little as 2.5 kg for smaller breeds or even up to 10+ kg for larger ones. Weight can also fluctuate during different times of the day.

Weight depends on the cat’s breed, for example, the average weight for each breed are

  • Domestic cat – 3.5 to 4.5kg
  • Persian –  3 – 5.5kg
  • Siamese 2.2 to 4.5kg
  • Maine Coon 4.5 to 11kg

Instead of aiming for a specific number that your cat should weigh, it’s best to focus on their body condition score. This will better help you to determine overall fat content versus muscle mass which is more closely related to the health of your cat. Focus on numbers only when your cat is in the middle of a weight loss or weight gain program to better keep track of their progress.

Feline Body Condition Chart

How to Determine if Your Cat is Overweight

Our domestic kitties have gotten bigger and bigger over the years. So much so that an overweight cat is actually viewed as normal and most cat parents don’t realize that their pet’s health may be in jeopardy. To determine if your cat is overweight, look at their body condition score. This is based on the amount of fat on a cat’s body. A few target areas to look at are over the ribs and your cat’s waist. Using a body condition chart will help you as well.

  • Ribs: When you feel your cat’s ribs, the first few closest to their front legs should have some padding over them. It should feel similar to the back of your hand. As you move further towards your cat’s waist or hind legs, you should be able to easily feel those ribs. They shouldn’t be visible under their haircoat but easily felt.
  • Waist: When you look at your cat from above, they should have an hourglass figure. The waist should be narrower than the shoulders and hips. When viewed from the side, their waist should also tuck up rather than hanging down from that ribs. Most overweight kitties will also have that pendulous fat pad covering their abdomen that can hang down and swing side-to-side when they walk.
  • Neck: If your cat wears a collar, you may find yourself loosening it as they gain weight.
  • Other: Other signs of weight gain include a decrease in activity and grooming. Your once prim and proper cat may not be able to reach their back to groom anymore and the hair may become matted and rough. Overweight kitties may also sleep more and become irritable, possibly because they don’t feel good.

How to Determine if Your Cat is Underweight

Finding out if your kitty weighs less than ideal can be done using the same method as above. Look at the ribs and waist in profile and from above. Often cats that are underweight will have a very defined backbone and hip bones that can even be visible through their hair coat. Long-haired cats can be tough as the hair will hide a lot of the first visible signs of skinniness so it’s important to always get your hands on them.

  • Ribs: For underweight cats, there will be very little or no padding over the ribs closest to the front legs. It will feel more like the knuckles on your hand when you make a fist. You may also be able to easily see the ribs closer to the tummy and hind legs.
  • Waist: An underweight cat will have a waist more like that of an ant, with a very defined tuck when viewed from the top or side. Sometimes their waist may only appear as wide as their backbone. You may also be able to see each vertebra and it’s hip and shoulder bones.
  • Other: Signs of weight loss in cats can be similar to those of weight gain. They may be less active and sleep more. They may groom less since they probably aren’t feeling well. Some will be ravenous and beg for food constantly, while others will leave a nearly full dish after every meal.
pet obesity infographic cats

How Excess Weight Impacts Your Cat

Overweight cats carry excess fat, which is more than just stored calories. Fat is actually a very active tissue that secretes inflammatory hormones and creates oxidative stress on cellular membranes. What does this mean exactly? It means that having extra fat hanging around can actually contribute to serious diseases, decrease a cat’s immune function, and make them feel generally bad. All of these contribute to a shorter lifespan, sometimes by as much as a couple of years. So, carrying extra weight isn’t just uncomfortable and unsightly for a kitty, it can actually be deadly. Let get a little more specific:

  • Diabetes mellitus: This is a disease of the pancreas. The pancreas is an organ of the digestive tract that has two main functions: to secrete enzymes that aid in digestion and to secrete insulin which regulates blood sugar. Diabetes in cats occurs when the insulin-secreting part of the pancreas goes haywire or when the cells in the body become no longer sensitive to the effects of insulin. Either way, blood sugar levels go unchecked causing rapid and extensive swings that can lead to tissue damage and even death.
  • Arthritis: Excess weight causes more wear and tear on joints. Excess fat can increase inflammation in those joints as well. This combination leads to a painful kitty that may be reluctant to move or exercise, causing a vicious cycle of weight gain and inflammation.
  • Urinary issues: The urinary environment is especially susceptible to inflammation. A cat’s diet and stress levels can lead to urinary stone or crystal formation, urinary tract infections, and dangerous urinary blockages. FLUTD (feline lower urinary tract disease) is a special circumstance in which cats repeatedly develop urinary tract infection-like symptoms without having an actual bacterial presence. Instead, these symptoms are based on inflammation brought on most commonly by stress and harboring excess weight.
  • Heart disease: While heart disease like that seen in people is fairly uncommon in our pets, excess weight does put extra pressure on the heart. Increased blood pressure is another common issue seen with overweight kitties that can impact and overwork the heart.
  • Respiratory difficulties: Overweight cats may experience trouble breathing, usually just due to an issue of space. Extra fat deposits put pressure on the chest, especially when a cat is lying down, making it difficult to fill the lungs and breathe.
  • Skin problems: If all of the above weren’t enough, heavy kitties may have more trouble with their skin. Again, fat secretes inflammatory hormones which can cause itchy, infection-prone skin. As cats gain weight, it also becomes more difficult for them to groom, especially hard to reach areas like their back, legs, and tummy, causing mats and snarls that can create sores.

How Being Underweight Affects Your Cat

Having a less than ideal body condition or being underweight is usually an issue of a kitty not getting enough groceries. This can be because they aren’t provided with that food or their body isn’t able to utilize it properly. Either way, not having enough food deprives your cat’s body of energy that is needed for growth, maintenance and repair.

  • Immune system: The immune system uses nutrients to build its protective army that helps keep your cat from getting sick. Without the required nutrients, the immune response may not be sufficient to protect your cat from everyday pathogens that they encounter, leading to more illnesses.
  • Decreased growth: Kittens require mass amounts of energy, partially because they burn a lot of it tearing around your house at all hours and partially because growth requires it. If a kitten is underweight, they won’t grow to their full potential and may be stunted or develop limb and other deformities.
  • Decreased productivity: Reproduction is considered a luxury, not an essential function of cats. When they are having a hard time meeting the energy requirements for other necessary bodily functions, they basically shut down the reproductive system so that it won’t leach energy from more important organs. This makes it hard for a cat to get pregnant and can cause abortions in a cat that is already expecting.
  • Increased injury: Muscles require protein for energy and upkeep. If that protein isn’t there, muscle mass will be depleted as the body starts to utilize muscle protein for other functions. A decrease in muscle mass can lead to weakness which can lead to injuries like sprains, strains, and ligamental tears.
  • Decreased activity: A cat that isn’t getting enough energy and that is lacking muscle mass isn’t going to be very active. Underweight kitties tend to conserve what energy they do have for more important things, like keeping their essential organs running, and less time playing or interacting with you.

What Causes Excess Weight in Cats?

Weight gain and excess weight is simply an increase in body fat. However, how that body fat gets increased can be anything but simple. In fact, there may be many reasons that a cat gains weight.

  • Overeating: This one’s pretty straight forward: if calories in exceed calories out (or burned), those extra calories get stored as fat. Many cat parents choose to feed their cat free-choice, meaning there’s always food available for them. While some kitties are great at self-regulating, many aren’t and will eat more than what they need.
  • Too many treats: We all want our feline friends to love being with us and what better way than by giving them a tasty treat each time they come near? Treats are added calories that often get overlooked in the above equation. If you choose to give human food to your cat, it’s important to know that table scraps or other people’s food are very high in calories, giving even small amounts a very calorie-dense punch. For example, a one-ounce piece of cheese to your cat is like you eating one and a half hamburgers, buns and all!
  • Too little exercise: We all know that cats, for the most part, aren’t willing participants in exercise. You can’t take them for an extra lap around the block or trip to the dog park to give them a little movement boost and so most cats fall into a little to no exercise habit. This becomes a problem when their feeding amount isn’t decreased to match their activity level. Again, if calories in exceeds calories burned, weight gain is going to occur.
  • Others: A cat’s age, gender, breed, and underlying medical issues can contribute to weight gain. Females and older cats tend to have a slower metabolism, making it harder for them to burn calories. Neutered or spayed animals also may gain weight more easily, and kitties with certain diseases, like thyroid issues or an injury, may pack on the pounds with a bit more vigor.

What Causes Weight Loss in Cats

Again, there are two main reasons that a cat is underweight: they simply aren’t getting enough to eat or their body isn’t able to utilize those nutrients properly.

  • Not enough food: Weight loss can be as simple as your cat isn’t getting enough to eat. This would be more common for those kitties that are outdoors or that share a food dish with a more aggressive eater that gets the majority of every meal.

They may also not be eating due to anxiety or stress that has them too nervous to eat. If you’ve recently moved or adopted another furry housemate, it could put a kitty off of their food for a while.

Pain, such as arthritis or dental disease, can cause a cat to eat less. It may be uncomfortable for them to chew or to stand at the food dish.

  • Medical issues: Many medical conditions can cause weight loss in cats. Topping the list are diabetes, kidney disease, hyperthyroidism, and cancer. Other issues that affect the digestive system, such as parasites or inflammatory bowel disease, can also lead to weight loss. Any sudden, unexplained weight loss should be looked at by a veterinarian.

How to Help Your Cat Lose Weight

The first step in getting to an ideal weight in your kitty is determining if they have a problem. This means visiting your vet and getting a body condition scoring and weight. Your vet will then be able to give you recommendations on a target weight and body condition. They will also be able to determine if your cat’s weight problem is the result of a medical condition that needs to be addressed.  Don’t start a cat weight loss diet, unless it was overseen by a Vet, as it might harm your pet rather than helping her.

Feed the Correct Amount of Food

From there, look at how you are feeding your cat. Oftentimes weight loss can be as easy as feeding the correct amount of food. Check your current cat food label. There should be a recommended feeding chart that will tell you the amount of food that a cat of a certain weight typically needs per day. Feed your cat for the weight that you want them to be, not the weight that they currently are. This will usually mean a cut in the amount of food that your cat gets per day. They may miss it and beg for more for a little while but will eventually settle in.

High Fiber Higher Protein Diet

If you’ve been feeding your cat correctly, you may need to look into a diet food that contains higher fibre and higher protein with fewer calories. This way you can keep your kitty feeling full while cutting their calories and hopefully helping them to drop weight. There are many low-fat formulations available and even some really heavy hitters that are available through prescription. Cut out the treats and instead incentivize your cat with a few bits of their regular kibble or some healthy vegetables, like cooked green beans or carrots, for those more adventurous eaters.


The final piece of the puzzle is exercise. The more calories your cat burns, the quicker the weight will come off. Look for fun, interactive games that your cat can do such as laser or light chasing, battery-operated toys, or even a cat tree or series of shelves that they can jump and climb on. Getting a furry playmate may also help if your cat is willing!

Regular Weigh-ins

Regular weigh-ins with your veterinarian will help encourage progress or pinpoint weight loss issues before they become a problem. It always helps to have a fresh set of eyes when your cat embarks on a weight loss journey, as the person who sees them every day might not notice any slight differences.

Another important part of the weight loss journey is the destination. When your cat makes it to that target weight and body condition score, it’s important to know how to maintain it. Often that is done through strict portion control and exercise, but it’s important not to take this step for granted or else you’ll be starting back at square one.

How to Help Your Cat Gain Weight

We all think that gaining weight has to be easier than losing it, but there is a trick to gaining a healthy weight versus gaining fat. If you’re trying to up the body condition of an underweight cat, you want that weight to be muscle, not fat. So, rather than feeding your kitty junk food, you should instead be looking at a high-quality protein boost.

Some kitties may just require more food. Try feeding free-choice or more frequent meals if this is an option with other pets in your household. You can also try to entice your kitty to eat by mixing in some canned food or some lean meats like chicken or fish.

Other options would be to give them a more calorie-dense food, like a kitten formula or a therapeutic food that provides all the essential nutrients with a little extra energy. Nutrient supplements in the form of pastes or powders may help as well.

how to change cat diet

We all want to keep our feline friends around as long as possible and will go to great lengths to ensure that they are kept safely indoors, are up to date on their vaccinations, fed the finest foods, and sleep on the coziest beds. But what we often overlook is their weight. As a cat parent, it’s necessary to understand the importance of your cat reaching and maintaining a healthy weight. Regular visits with your veterinarian to discuss your cat’s weight and body condition score are great ways to get the ball rolling, and diligent attention to cat food portions and exercise will help your cat to live the longest, fullest life possible.