Using the PetSci BMI Calculator to Calculate Your Dog’s BMI

The PetSci dog BMI calculator takes in to account the breed, height, weight and sex of your dog and then displays a BMI value. By itself this BMI value would be useless, as it is not comparable to a human’s BMI – however, because we’ve taken individual breed specifications into account we can give you a fairly accurate guide to whether your pet is underweight, overweight or are at an ideal weight.

At the moment, not all breeds are listed, however the number of breed will grow over time – or you can speed up the process by requesting for your dog’s breed to be added in the comments below!

If you want to skip on the science behind the dog BMI calculator and get right in to calculating click here to get started!

What is BMI?

BMI or body mass index is a value used to determine whether a human is overweight, underweight or an ideal weight for their size. The calculation is quite simple, weight divided by the height2.

In humans, a BMI of 18.5 or less is considered underweight, a value of 25 considered overweight. Values in-between indicate an ideal weight.

Unfortunately this scale can’t be used for dogs due to the massive variation between breeds! For example, an ideal BMI for a Chihuahua isn’t going to be ideal for a Great Dane!

The PetSci BMI Calculator

The PetSci BMI calculator uses breed specifications to determine an upper and lower BMI value – values above are the upper value is considered overweight, values below the lower value are considered underweight.

But what does all this mean?

Simply, if your dog is a pedigree breed then it is possible to work out whether or not they are over/underweight depending on their height and weight.

The BMI calculator has been tested on a number of real-life scenarios, with people’s pets of various breeds and weights – in each situation height, weight, sex and breed were obtained. This was put in to the calculator and the results were given. The weight status (i.e. underweight, overweight or ideal weight), determined by body condition scoring, matched the results from the PetSci BMI calculator, great news!

Body Condition Scoring

There are two body condition score scales, 1-5 and 1-9. Both however are essentially the same. On the 1-5 scale, a score of three (where the ribs can be felt) is ideal. On the 1-9 scale, a score of 4 or 5 is ideal. The image below, courtesy of Purina, gives you an idea on what constitutes an overweight/underweight/ideal weight dog.

calculating your pet dogs bmi body condition score

What if I Get an Overweight Result?

Don’t be put off if you get a result that says your pet is overweight! Try adding some extra exercise to their daily routine (encouraging extra activity, longer walks, etc.) or try switching them to a calorie controlled diet. Remember though, to consult your vet before making major changes to your dog’s diet.

Your Feedback!

Please take the time to try out our pet BMI calculator, it is very easy to use and is a great guide for determining your pet’s weight status.

Let us know if you agree with the results, we think you will! If you want your dog’s breed added to the calculator, please don’t hesitate to let us know in the comments below!

Click here to get started with the dog BMI calculator


About James Watts

BSc Bioveterinary Science. Editor of PetSci. When I'm not writing, learning, discussing, or reading about animals, you know it's the weekend! Currently developing PetSci HealthTrak, the fast and easy way to monitor your pet's weight and calorie intake. HealthTrak offers a simple way to track your pet's progress, helping them achieve a healthy weight and a long, happy life.

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  1. Hi can you add Northern inuit to the list they are like a husky but not quite

  2. Is there a chart one can follow to know which body score will be in the overweight category and which will be under or ideal?

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