Your dog sadly doesn't live as long as you, but they still live a full life — just on a different timeline. To keep track of the timeline, many people like to calculate it from dog years into human years.
The phrase "dog years" refers to the calculation of how old a pup actually is, versus how old a pup is on a "human years" timeline. The myth-based formula multiplies a dog's age by seven to get its approximate age if it were to be a human.
However, according to veterinarians, this calculation isn't always accurate.
Is calculating your dog's age to human years accurate?
Dr. Jo Myers, a veterinarian at veterinary telemedicine company Vetster, said multiplying how old your dog has been alive by seven is a reasonable starting point to understanding how dogs age faster than humans, but it's an over simplification.
"Dogs don’t age at a steady rate that’s seven times faster than humans age. They mature remarkably quickly early in life, and their rate of aging later on varies considerably, especially with their size. There’s plenty of individual variation, too, just as there is among people of the same age," said Myers.
The one-to-seven formula doesn't necessarily work due to several factors.
First, it completely depends on their size. Myers said smaller dogs tend to live longer than bigger dogs, making their lifespans completely different.
Second, a dog's life isn't completely linear. Natascha Hedegaard, an in-house veterinary advisor for JoyFull Pet, said large and giant breeds have a longer juvenile stage than small breed dogs. Then, bigger dogs age quicker after the first 2 years, but it leads to a shorter lifespan.
These factors, including varying breeds, make the old wives tale of multiplying a dog's age by seven inaccurate.
How to calculate your dog's age to human years
When it comes to measuring the age of your dog compared to a human life, there isn't a one-size-fits-all formula.
Hedegaard said veterinarians measure a dog's life in phases, and Myers said it's best for everyone to calculate it in phases, rather than ages. One calculation Myers recommended was the American Animal Hospital Association’s Canine Life Stage Calculator, which doesn't give an exact age, but a stage of life.
The stages of life are puppies, young adults, mature adults and seniors. These stages can help owners understand what their dogs might need.
For example, Myers said a puppy has different nutritional, behavioral and preventive healthcare needs from an adult, whose needs are focused on maintaining a healthy body and muscle condition, dental health and early detection of disease.
That said, Myers said this tool can vary, as pups can be in different health in the same stage of life.
When it comes down to calculating dog to human years, Myers said there isn't a biologically precise conversion, but the idea isn't useless.
"Thinking in terms of puppy, young adult, mature adult, and senior gives us useful 'buckets' to put dogs of a similar age into that are easy to relate to our own lived experience. We understand that a child, a young adult, a middle-aged adult, and a senior are at different points in life, while also understanding that people within each of those groups can vary tremendously. The same idea works well for dogs," Myers said.
This article originally appeared on USA TODAY: What are 'dog years?' Here's how to properly calculate them
