How Many Calories Does a Cat Need a Day? Chart by Weight and Age

How many calories does a cat need a day? For a healthy, neutered adult cat, the usual veterinary estimate is 70 × (body weight in kg)^0.75 × 1.2. For a 10 lb cat that’s about 260 kcal a day. Cats have small daily budgets, so a few extra treats or a heaped scoop of kibble can tip the balance, and knowing the number makes portions much easier to get right.

This post covers the formula, a cat calorie chart by weight, a worked example with our cat calorie calculator, how kittens and senior cats differ, and how to check the result against your cat’s body shape.

How do you calculate a cat’s daily calories?

It takes two steps, the same method vets use for dogs.

1. Resting energy requirement (RER). The energy your cat uses at rest:

RER = 70 × (body weight in kg)^0.75

2. Maintenance energy requirement (MER). Multiply the RER by a factor. These are the cat factors from the Merck Veterinary Manual:

Cat	Daily calories
Neutered adult	1.2 × RER
Intact adult	1.4 × RER
Obesity-prone adult	1.0 × RER
Kitten	2.5 × RER (or free choice)

The cat factors are lower than the dog ones (a typical neutered dog starts at 1.4–1.6). If you use a dog calorie calculator for a cat, you’ll overfeed.

Merck and Ohio State’s veterinary nutrition service both stress that this is a starting estimate. The needs of two cats of the same weight can differ by 30% or more, so you adjust from here based on your cat’s weight and body condition.

Cat calorie chart by weight

This chart uses the same formula as our calculator. Use your cat’s ideal weight if it’s overweight.

Cat’s weight	Resting (RER)	Neutered adult (1.2×)	Intact adult (1.4×)	Inactive or easy gainer (1.0×)
6 lb (2.7 kg)	148	178	208	148
8 lb (3.6 kg)	184	221	258	184
10 lb (4.5 kg)	218	261	305	218
12 lb (5.4 kg)	249	299	349	249
14 lb (6.4 kg)	280	336	392	280
16 lb (7.3 kg)	310	371	433	310

A 16 lb cat has nearly three times the body weight of a 6 lb cat but needs only about twice the calories. That’s the 0.75 exponent at work: energy needs rise more slowly than weight.

Worked example: a 10 lb neutered indoor cat

Here’s what our cat calorie calculator shows for a 10 lb, neutered adult cat:

1. Convert to kilograms. 10 lb × 0.4536 = 4.54 kg.
2. Resting energy. 4.54^0.75 ≈ 3.11, and 70 × 3.11 ≈ 218 kcal.
3. Apply the factor. 218 × 1.2 ≈ 261 kcal. The calculator rounds this to 260 kcal a day.
4. Starting range. It suggests 235–285 kcal (±10%), and weighing your cat monthly.
5. Treat budget. 10% of 261 is about 26 kcal.

To turn calories into food, divide by the calories per can or per cup printed on the label. Our cat food calculator splits the total between wet and dry food for you, and our guide on how much wet food to feed a cat explains the wet and dry split.

How does this compare with WSAVA’s ranges?

The World Small Animal Veterinary Association (WSAVA) publishes calorie ranges for an average healthy adult cat in ideal body condition, based on the 2006 National Research Council equations. Here they are next to the neutered-adult formula:

Cat’s weight	WSAVA range	Neutered adult (1.2 × RER)
3 kg (6.6 lb)	200–210	191
4 kg (8.8 lb)	225–250	238
5 kg (11 lb)	250–290	281
6 kg (13.2 lb)	265–330	322
7 kg (15.4 lb)	280–370	361

For cats, the two methods agree well. From 4 to 7 kg the formula falls inside WSAVA’s range, and for a small 3 kg cat it’s a little below. So if your cat is small and at a healthy weight, don’t be surprised if it holds its weight on slightly more than the chart says.

What changes how many calories a cat needs?

• Neutering. The 2021 AAHA nutrition guidelines say energy needs fall after spaying or neutering, so portions usually need to come down. That’s the drop from 1.4 to 1.2 × RER.
• Indoor life. The Cornell Feline Health Center notes that cats living strictly indoors burn fewer calories than cats that go outside, and that cats fed from a bowl burn fewer than feral cats, which have to hunt.
• Breed. AAHA lists breeds such as Persians and Norwegian Forest Cats among those prone to weight gain.
• Growth. Kittens need about 2.5 × RER, or can be fed free choice, according to Merck. A 4 lb kitten works out to about 275 kcal a day in our calculator, more than many adult cats.
• Age. This one is less predictable in cats than in dogs. See the next section.

Do senior cats need fewer calories?

Not always. The 2023 AAHA Senior Care Guidelines say cats’ maintenance energy needs tend to decrease up to about age 10 and then start to increase, although the published data vary a lot. The reasons are worth knowing:

• Many older cats digest food less efficiently. AAHA reports that protein is less digestible in 20% of cats older than 11 years, and fat is less digestible in up to 33%.
• Cats can lose up to 33% of their lean body mass between 10 and 15 years of age.
• AAHA notes that a cat’s ideal body condition score, up to 6 out of 9, can be associated with a longer life, while underweight cats have greater health and survival risks.

AAHA suggests healthy senior cats may need more energy-dense, higher-protein, highly digestible food, offered in smaller meals more often. So if your older cat is slowly getting thinner, don’t assume it’s just age. Our post on cat years to human years explains when a cat counts as a senior (over 10) and how often seniors should see the vet.

How do I know if my cat is eating the right amount?

1. Weigh your cat monthly. A baby scale or weighing yourself with and without the cat works.
2. Check body condition. You should be able to feel the ribs under a thin layer of fat and see a waist behind the ribs from above.
3. Adjust by about 10% if the weight is drifting, and recheck in a month. Small changes matter: 10% of a cat’s day is only about 26 kcal.
4. Count the extras. AAHA recommends keeping treats and table food to 10% or less of daily calories.
5. Don’t crash diet. If your cat needs to lose weight, plan it with your vet. Our calculator’s weight loss setting (0.8 × RER at the ideal weight) is meant to be used under vet supervision. Our post on how fast a dog should lose weight has a section on the safe pace for cats.

When to call your vet

• Your cat is losing weight without trying, especially if it’s over 10.
• Your cat stops eating, or eats much less than usual, for more than a day.
• Your cat is gaining weight steadily even though you’ve cut portions.
• Your cat has a medical condition such as kidney disease, diabetes or hyperthyroidism, or is pregnant or nursing. The standard formula doesn’t apply.

For dogs, the method is the same but the factors are higher. See how many calories a dog needs a day.