0 comments / Posted on by Dogs Corner

Convert-5-dog-years-to-human-yearsHow to convert 5 Dog years to Human years

Meet Otto

Last week I had a chance to have a conversation with a good friend of mine Brett. Like most Australians he is currently in self isolation that allows him to spend more time with his beloved family and a playful dog Otto. Otto is an English Foxhound who has been a loyal companion to his owner, going out for walks in the park, playing fetch with many toys, and patrolling the area of his home, watching for any wild animals that pass by.

Brett and his family just celebrated Otto's 5th birthday, and my friend asked me if I know how to convert 5 dogs years to human years. His family noticed that some of their four-legged friend activities have been reduced in the last 6 months, and they are concerned with the overall health of Otto. He used a widely accepted formula and assumed that Otto is 35 years old in human years. I didn't have my phone with me to show the dog age calculator we developed recently. Instead, I tried to explain how this calculation works and why simply multiplying your dog age by 7 won't give you correct result. It is widely believed that a single dog year in age is equal to 7 years in a human being, but the fact is that this 7-to-1 ratio is totally wrong. To properly calculate how old a dog is in comparison to a human’s age, you must base these calculations on the size of the dog and its breed.


Dogs are a diverse species of mammals, varying in height and weight, coming in many shapes and hair types. There is a lot of variation among breeds regarding life expectancy. In Otto’s case he is a large hunting hound, and larger breeds of dogs are known to age faster when they reach the age of 5. An English Foxhound at 5 years old is the same as being 40 years old in human years.

Using the Dog Years to Human Years Calculator, you will notice the difference in the ages of each dog breed. Small dogs reach adulthood faster than big dogs as they reach skeletal and reproductive maturity sooner. Small dogs have a shortened juvenile period and an extended adulthood. Large dogs may take 2 years to reach their completely mature skeletal body size and then they may only have another 4 or 5 years of life. Great Dane, Bulldog, Rottweiler and Saint Bernard are the perfect examples of the dogs with the shortest lifespan. If you own a Bernese Mountain Dog or an Irish Wolfhound than I might have bad news for you - due to their gigantic size, these breeds live no more than 7 years on average.

Basic Principles

Knowing that smaller dog breeds have a tendency to age faster in their first 2 years of life and then their aging process slows down, the opposite is true for larger dog breeds. Here is how to calculate your dog’s true age. For the first 2 years of a dog’s life, you count 12.5 years per human year for small dogs, 10.5 years per human year for medium-sized dogs, and 9 years per human year for large dogs. After turning 3 years old, the aging process varies for all dog breeds. Small dogs like Dachshunds, Beagles and Pugs will age by 4.32, 5.20 and 5.95 years per human year respectively. Large dogs like the German Shepherd and the Boxer will age by 7.84 and 8.90 years per human year respectively.

Back to Otto and how to convert 5 dog years to human years. At 2 years of age, Otto would be 21 to 22 in human years, 10.5 or 11 multiplied by 2. If he is 40 years old in human years at the age of 5, that means that Otto will age by 18 or 19 human years in the next 3 years of his life. To calculate this, you take the 19 human years and divide it by 3 dog years. The answer is that Otto will age by 6.33 years per human year, or simply 18 divided by 3 equals 6.


English Foxhounds normally weigh 60 to 75 pounds (roughly 28 to 34 kilograms), which is in the large dog breed range, but Otto’s aging process fits more along the lines of medium-sized dogs. After turning 3 years old, Staffordshire Bull Terriers age 5.33 years per human year, Spaniels age 5.46 years per human year, and Labrador and Golden Retrievers age 5.74 years per human year. Paying close attention to his health, Otto should be able to live a long life in the range of 10 to 13 years of age. No matter what size your dog is, treating your loyal companion with great care will allow it to live a long and happy life.


Leave a comment

All blog comments are checked prior to publishing