Dog Food Calculator

Dog with Dog Food Calculator and Notepad

The Dog Food Calculator below can help you estimate the proper serving size for your pet. It’s based upon a study published by the respected Waltham Centre for Pet Nutriton in Leicestershire, England.1

To use the calculator, you’ll need to know your dog’s ideal weight. This is what you believe your pet should weigh.

You’ll also need to know the number of calories in the specific dog food you’re feeding him.

Dog Food Calculator
Step 1
Your dog's ideal weight

pounds   kilograms

Step 2
Your dog's activity level

Step 3
Your dog food's calories per serving

kcal / cup

The calculator’s formula2 uses a dog’s metabolic weight to suggest an approximate serving size.

Dog Food Calculator
Guidelines

The Dog Food Calculator was designed for adult dogs only… not for puppies. 

And it should never be used for pregnant or lactating females.

Small breeds are considered adults at about 9 to 12 months of age. And medium breeds at about 12 to 14 months.3

However, large and giant breeds shouldn’t be fed as adults until they reach around 1 to 2 years — depending upon the breed.4

Overweight Dogs

If you believe your dog might be overweight, be sure to choose the “Overweight” option for “Your dog’s activity level”.

Otherwise, the recommended serving size will likely be too high.

And for help, be sure to visit our Best Dog Foods for Weight Loss article.

Senior Dogs

Older dogs have significantly lower energy needs than younger ones. So, it’s easy for them to put on extra weight.

In general, small to medium dogs are considered seniors at about seven years of age.  However, larger breeds reach senior status much sooner — some as early as five.5

Converting From Calories
to Serving Size

Once you’ve entered your dog’s ideal weight and activity level, you’ll know the number of calories per day.

However, to convert calories into something you can use, you’ll need to enter the number of calories in your dog’s food.

The number of calories in a given amount of dog food is known as its metabolizable energy (ME, for short). It’s usually reported somewhere on a dog food package like this…

  • Calories per cup (kcal/cup)
  • Calories per kilogram (kcal/kilogram)

By the way, the calculator assumes you’re feeding your dog just once a day.

If you prefer to feed your dog twice a day, be sure to divide your result in half so that both meals add up to the full daily calories suggested.

The Bottom Line

Since every dog is unique, it’s impossible to predict the serving size that’s perfect for each pet.

So, start with the package’s feeding instructions — or the amount suggested by our calculator.

And be sure to weigh your dog every few weeks.

Then, simply adjust that suggested serving size up or down to reach and maintain your pet’s ideal weight.

Sure, it’s a little work. But in the end, it’s the only real life method you can scientifically rely on.

Final Word

This tool is intended for educational purposes only and should not be used as a substitute for professional veterinary advice.

Footnotes

  1. Waltham Centre Pocket Book of Essential Nutrition for Cats and Dogs (2009), Energy Requirements of the Adult Cat and Dog, p. 8
  2. ME (kcal/day) = 110 (body weight in kilograms)0.75 to maintain a typical adult dog
  3. Iams, “How to Transition Your Puppy to Adult Food
  4. Waltham Centre for Pet Nutrition (1999), Canine Life Stages and Lifestyles, The Waltham Course on Dog and Cat Nutrition, p. 4
  5. Waltham Centre for Pet Nutrition (1999), Canine Life Stages and Lifestyles, The Waltham Course on Dog and Cat Nutrition, p. 16