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Home > Cats > How Many Calories Does a Cat Need? With Easy to Use Calculator

How Many Calories Does a Cat Need? With Easy to Use Calculator

a calico cat eating from metal bowl at home

As cats have individual dietary needs, finding the right food is only half of the battle. Feeding the proper amount is just as important to a healthy feline diet. Your vet will tell you that malnutrition and obesity are directly related to the well-being of your pet. But how many calories does a cat need every day?divider-paw

Why Do I Need to Calculate My Cat’s Calorie Needs?

To determine how many calories a cat needs in a day, we usually refer to the label on the food bag or can. It spells out, based on weight, how much to feed. Sometimes, those labels even differentiate between age groups or activity levels. What those labels can’t take into account is each individual cat’s needs. Neutered and spayed cats often have lower caloric needs than intact cats. Indoor cats require less than outdoor cats, and a cat that spends all day bouncing around the house requires far more than the cat that sleeps on the couch all day.

By learning how to calculate your cat’s calorie needs, you’re identifying the correct amount of food your cat needs to stay healthy. You can always tweak up or down if needed, but a base knowledge of what your cat needs will help you have a baseline to work with. It also gives you the knowledge of how to adjust your cat’s feeding with life changes, weight changes, and medical changes.

Calculating Calorie Intake for Your Cat

To calculate your cat’s calorie needs, you’ll need an accurate weight on your cat. Guessing their weight or going off of their vet visit from last year can lead to inappropriate feeding. The following equation allows you to determine the resting energy requirements, or RER, for your cat. This is the baseline calorie need for the energy your cat burns while at rest, so it basically accounts for your cat staying relatively sedentary most of the day except for a few trips to the litter box, food bowl, and different locations in the home.

RER in kcal/day = (ideal or target weight in kg ^ 0.75) x 70 OR 30 x (body weight in kg) +70

To determine your cat’s weight in kilograms, divide its weight in pounds by 2.2. A 10-pound cat is 4.5 kg.

The calculator itself does not consider your cat’s age, current weight, or activity level, but the site does provide additional recommendations based on these. It’s extremely important that you consult your veterinarian and have your cat health tested before you make significant dietary changes. Underfed and overfed cats can develop health issues, and sudden changes in calorie intake can lead to some dangerous problems. Also, your veterinarian will be able to give you a target weight for your cat that you can use in the equation.

Image Credit: Viktor Lugovskoy, Shutterstock

Additional Factors That May Alter Your Calculation

Spaying/Neutering: Cats that have been fixed produce fewer hormones, like testosterone and estrogen. This causes a dip in their metabolism and when testosterone levels decrease, muscle production is more difficult in both males and females.

  • To determine the calorie needs of a fixed cat, use this equation: RER x 1.2

Intact Adult: Intact cats retain the hormones that fixed cats have lost, so they are less likely to gain weight. In fact, they usually have a much higher metabolism than fixed cats, which significantly increases their calorie needs.

  • To determine the calorie needs of an intact adult cat, use this equation: RER x 1.4

Sedentary/Obesity Prone: Is your cat lazy but at a healthy weight? If they spend most of their time sleeping or they’re up performing routine tasks, then your cat falls into this category. If your cat parkours to the food bowl twice a day, then they probably don’t fit this category.

  • To measure the calorie needs of a sedentary cat, use the RER you already calculated.

Weight Loss: If your cat has been cleared by your veterinarian for weight loss, use the following equation and run the results by your vet for verification: RER for ideal weight x 0.8

Weight Gain: Don’t put your cat on a weight gain diet without checking with your veterinarian first. Many people are unfamiliar with how to determine the body score of a cat and may think a healthy weight cat is too thin.

  • Use the following equation to determine the weight gain needs of an underweight cat: RER for ideal weight x 1.8

Kittens Under 4 Months: Tiny, growing kittens have high calorie needs.

  • Use the following equation: RER x 2.5

Kittens 4 Months to 1 Year: Older kittens and juveniles have a greater calorie need than adults.

  • Use the following equation: RER x 2

These calculations and more information can be found here.

How Many Calories Does a Cat Need?

There’s no one-size-fits-all solution to the problem. However, we built this calorie calculator to give you a rough estimate of what to expect.

The exact amount of calories an individual animal needs to maintain a healthy weight is variable and influenced by many factors including genetics, age, breed, and activity level. This tool is meant to be used only as a guideline for healthy individuals and does not substitute veterinary advice 

What Counts Toward My Cat’s Daily Calorie Intake?

Everything you feed your cat should count toward their calorie intake! Many people make the mistake of feeding an appropriate amount of dry food, but then provide treats or wet food throughout the day. Treats are relatively low in calories, but if your cat’s calorie need is 200 calories per day, and you feed them 10 treats throughout the day at 5 calories each, then you’ve given your cat a quarter of the daily calorie need just in treats. Table scraps, treats, and nibbles of the food you accidentally left on the table all count toward your cat’s calorie intake. Just like with people, the idea that “if it’s not on my plate then the calories don’t count if I eat it” doesn’t work here.

How Often Should I Feed My Cat?

If your cat self-regulates its own feeding schedule, then free feeding is the best option for cats. Cats are made to graze on small amounts multiple times per day to keep their body functioning at its best. You don’t need to fill up the bowl for free-feeding cats, though. You can put their allotted calorie intake for the day in the bowl and refill it daily.

However, some cats can’t be trusted with a full bowl of food. For these cats, feed them twice a day at least, but if someone is home during the day or you have an electronic feeder, provide a meal or two during the middle of the day. Frequent, small feedings help regulate blood sugar, liver function, and metabolism.

Suggested Calorie Intake for Cats By Weight

Kittens Under 4 Months: These growing babies usually need between 310–580 calories per day. Your kitten should gain approximately 1 pound per month.

Kittens 4 Months to 1 Year: While still growing, these kittens need between 250–360 calories per day. Your kitten should continue to gain approximately 1 pound per month through 8 months of age, and then weight gain should slow significantly.

10-Pound Fixed Cat: An average adult cat of this size that has been spayed or neutered needs approximately 200–240 calories per day. Your cat should maintain this weight with this calorie intake.

10-Pound Intact Cat: An average adult cat of this size that has not been spayed or neutered needs approximately 200–290 calories per day. Your cat should maintain a healthy weight with this calorie intake.

20-Pound Obese Cat: If your cat is obese at 20 pounds and has been cleared by a veterinarian for weight loss, its calorie need should be between 270–340 calories per day. The goal with weight loss for a cat is no more than 0.5 pounds or 1–3% of its body weight per month.

The Dangers of Obesity/Malnutrition in Cats

Cats suffering from obesity can develop joint pain and arthritis, as well as problems with their internal organs, including the spleen, which leads to diabetes. Obesity decreases their mobility and quality of life by making it more difficult to play and jump to preferred locations. However, you should never attempt a weight loss plan for your obese cat without consulting your veterinarian first. Rapid weight loss can also lead to medical problems and stress on the cat’s body.

Malnutrition doesn’t always refer to skinny cats! An obese cat is often malnourished due to not meeting all their nutritional needs. Cats that are underweight are frequently malnourished as well, unless there is a medical reason for their low weight. A vet visit should be your first stop for a cat that is too thin. Parasites, endocrine disorders, and tumors can lead to weight loss in cats. Also, check with your vet to determine if your cat actually is underweight or malnourished. Malnourished cats can experience weakness, lethargy, and permanent internal organ damage.



Determining how many calories your cat needs is surprisingly simple once you’ve played around with the equation. Check with your vet before making any changes in your cat’s diet, especially if you are switching from one type of food, like kibble or wet, to another type of food, like raw. Your vet will give you the best guidance for safely and appropriately feeding your cat, ensuring they stay healthy and happy in your care.

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Image Image Credit: Jaromir Chalabala, Shutterstock

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