How Many Calories Does a Dog Need?

Published Oct. 31, 2023

A Jack Russell Terrier holds a food bowl in their mouth.

What Are Calories and Why Are They Important?

Calories are a measure of the energy content of food. You may also see them referred to as kilocalories (kcal), but in nutrition circles, a kilocalorie and a calorie are the same thing.

Calories are the fuel that powers a dog’s life. They come from the fats, proteins, and carbohydrates a dog eats.

If a dog eats too few calories, they will lose weight as the body burns fat, and eventually muscle, to supply the energy missing in their diet.

When a dog consistently eats more calories than they need, they will gain weight as the extra energy is stored as body fat.

How Many Calories Should a Dog Eat?

So exactly how many calories should your dog eat? Unfortunately, there isn’t a one-size-fits-all answer to this important question. Many factors come into play.

Breed

Size is the main factor that determines how many calories a dog should eat. Big dogs need more calories than small dogs—it takes more energy to power a big body in comparison to a small body.

Breed can also play other roles in your dog’s calorie needs.

For example, when it’s cold a dog who has a thick, double-layered coat, like an Alaskan Malamute, will need fewer calories to stay warm than a similarly sized dog with a thin coat, like a Boxer.

Age

Puppies require more calories than adult dogs of the same size.

Puppies are growing and developing quickly, and that requires extra energy. A puppy’s calorie needs are highest when they are less than 4 months old.

After that, their calorie needs gradually decrease until they are done growing and end up at their adult level.

Senior dogs tend to need fewer calories than they did when they were younger. The bodies of older dogs tend to be less muscular, and muscle requires more energy to maintain than fat.

Body Type

A dog’s body type is another important consideration.

Highly muscular dogs need to take in more calories than less muscular dogs who weigh the same amount, because muscle burns more calories than fat.

Spay/Neuter Status

When a dog is spayed or neutered, their calorie needs decrease, probably because sex hormones help maintain a dog’s muscle mass and can also increase activity levels.

Unspayed females who are pregnant or nursing will require many more calories, since they are supporting their puppies in addition to themselves.

Activity Level

A dog’s activity level is another important factor in determining how many calories they should take in.

A dog who gets a lot of exercise may need twice as many calories—maybe even more—in comparison to what they would need if they were less active.

Individual Variation

It’s also important not to overlook the variations among individual dogs or even within one pup over time.

Due to differences in their physiology, some dogs simply have higher metabolic rates and burn more calories than others.

Certain medical conditions can also affect caloric needs. Your previously thin dog may develop hypothyroidism, a condition that leads to a reduced metabolic rate, and start putting on extra weight.

How To Calculate Your Dog’s Caloric Needs

You can get a general idea of how many calories per day you should be offering your dog.

Let’s use a typical 50-pound, neutered male dog as our example as we work through the calculations.

Convert your dog’s weight in pounds (lb) to their weight in kilograms (kg) by dividing by 2.2.

Weight in pounds/2.2 = Weight in kilograms
50 lb/2.2 = 22.7 kg

Insert your dog’s body weight in kilograms into this equation to determine their resting energy requirement (RER) in calories per day.

RER (calories/day) = 70 x (BWkg) 0.75
RER (calories/day) = 70 x (22.7) 0.75
RER (calories/day) = 70 x 10.4
RER (calories/day) = 728 dog calories per day

Use one of the following multipliers to convert your dog’s RER to their maintenance energy requirement (MER) in calories per day:

Typical spayed or neutered dog	1.6
Typical unneutered dog	1.8
Dog who needs to lose weight	1
Dog who needs to gain weight	1.7
Light exercise	2
Moderate exercise	3
Heavy exercise	6
Puppy (less than 4 months old)	3
Puppy (more than 4 months old)	2

RER (calories/day) x multiplier = MER (calories/day)
728 x 1.6 = 1165 dog calories per day

To account for normal variation, we need to create a typical range of calorie needs for a dog of this size, which is 25% less or 25% more than the number we’ve calculated.

Normal MER range = (0.75 x calculated MER) - (1.25 x calculated MER)
Normal MER range = (0.75 x 1165) - (1.25 x 1165)
Normal MER range = 874 - 1456 dog calories per day

Fortunately, you don’t have to do all this math by hand.

An online calorie calculator for dogs will do the work for you, or you can refer to a chart that lists typical calorie ranges for healthy adult dogs.

But if your dog is not typical (they have health problems, for example), online resources may not give you good information. If you need a puppy food calculator, don’t use an adult dog calorie calculator.

Instead, talk with your veterinarian about the appropriate number of calories to feed your dog.

Understanding Weight Control and Nutrition

So, why is this all so important?

If your dog is eating so little that they aren’t meeting their calorie needs, they will lose weight, lack energy, and may suffer from other nutritional deficiencies.

If you feed your dog too many calories, they will become overweight or obese and could develop one or more of the health problems associated with this all-too-common condition in dogs.

Work with your veterinarian to choose a healthy dog food—like Canidae Pure® with Wholesome Grains Real Beef & Barley Recipe Adult Dry Dog Food or Purina One® True Instinct Natural High Protein with Real Turkey & Venison Dry Dog Food—and ask them how much you should be feeding your pup.

If your dog’s diet is deficient or they have health problems, your veterinarian may also recommend a dietary supplement.

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