How To Compute A Dog's Age

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How To Compute A Dog's Age

June 11, 2023 4 min read

How To Compute A Dog's Age

The age of a dog is determined by how old they are when they are born. The average weight of a dogs is between 20 and 25 pounds.

If you have a older dog, then you can use the same formula to determine their age as a young dog. This includes determining their size, whether or not they are normal in terms of behavior, if they have any health issues, and how old they look.

This article will talk about how to compute a dog’s age using some basic math and some visual observation. Both methods are useful so do not worry about which one you should use.

Basic Dog Math: How Old Is My Dog? Using the Average Rule (aka UsingNParks)¶ The average rule way to compute the age of a dog is to take their weight and divide it by the length of their longest bone. This rule was created based on data that takes into account dogs that are short on one piece of bone or in one area of their body.

Add 1 year for each month the dog was alive prior to the first of the current month

A Pug in Dogs Clothing in a Park


This may seem odd to add years to a dog’s age, but it is important to do so for several reasons. One is that dogs can have a shorter life expectancy than we think.

The average dog has a life expectancy of about 5 years, and in the first year of that, they are only about 3–4 months old. After the first year, their life expectancy increases slightly due to healthy old age, again making it important to compute the dog’s age.

Another reason to add years is that dogs who are close to retirement age may need help getting ready for a next stage in life. For example, a 7-year old who is at the point where they don’t want to learn new tricks or changes in routine might be ready for adoption.

Adding years can be difficult when you do not have an older dog to compare yours to.

Add 1 day for each day the dog has been alive

Shallow Focus Photography of Adult Black and White Border Collie


When the dog is five years old, he or she may still be living a very active life. At five years old, a dog can run up to 30 to 45 miles per day, which is enough time to add one day to their age.

This does not mean that the dog was ever that young. It could be that he or she was raised in a home with other dogs that grew up in the same environment as they did. Or perhaps this dog was owned by a younger person, who enjoyed what they were doing together and how long they liked it.

It is important to note that this does not apply to older dogs that still enjoy activity. If your dog has already lost some of his or her desire to exercise, then this calculation does not apply!

If your dog has an accurate age estimate, it can help determine if you need to get them treatment or surgery.

Divide the number of days the dog has been alive by the number of days in a year

How to compute a dog's age

This calculators can help you compute the age of your dog. The number of days a dog has been alive is determined by how long they have been walking, playing, and living.

The number of days in a year is the date a dog was born, adopted, or entered into a program such as a puppy program or adult program. The date of adoption is the date when you became their owner

To calculate the age of your dog using this calculator, enter their name, the year they were adopted, and their current date. Then click on Add Years to determine how many years your dog has been living.

This calculator can be used both in conjunction with general vet care and pet care regimens to find the age range for dogs.

Multiply by 12 and add it to the answer from step 4

Photo Of Different Puppies


This is the most complicated step of computing a dog’s age. At this point, you can calculate the number of years your dog has lived!

The answer to how long your dog has lived is based on the number of years he or she has beenhousehold-familiar. This includes getting walked, attending a veterinary visit, and living with family members or owners.

To calculate the average age of a dog, you need to know the number of years it has had its life outside of its home. You can then add up all its ages and divide that amount by itself to get an average age.

This can be tricky to do as some ages are slightly higher or lower than the average. For example, a ten-year-old German shepherd might have an age when he was five that was above average.

Another way to calculate the average age is to subtract the oldest age from the rest and multiply by four. This subtracts out anyanzesthat may be older than four months old.

Cindy PetsForLife
Cindy PetsForLife

Hello, I'm Cindy, the founder of PetsForLife. I am a true animal lover with 3 cats and 1 dog of my own. My passion for all things pets has led me to create a unique collection of personalized pet gifts. Check out our personalized pet gifts on our website.

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