Dog Years Aren’t As Simple As They Seem — Scientists Say Your Pup May Be Older Than You Think

Everyone knows that one year for humans is the supposed equivalent of about seven dog years, meaning that dogs age roughly seven times faster than humans do. Lots of pet owners attempt to figure out their pets’ “real” ages by simply multiplying the number of years old they are by seven. And this sort of works, at least some of the time.

However, recent research is showing that the calculation most people use for dog years is actually pretty inaccurate. This is because dogs age very quickly at the beginning of their lives and then slow down in their later years. That means your dog could still technically be a puppy and actually already be approaching middle age!

Researchers investigated the DNA of more than 100 labradors of all ages, from puppies to 16-year-old dogs. They compared this data to more than 300 humans of different ages.

What the researchers learned was that a two-year-old dog is roughly age-equivalent (in terms of DNA aging, at least) to a 40-year-old human being. By the time a dog is 10, however, it has slowed down enough to be equivalent to a 68-year-old human.

Of course, this is different for different types of dogs. Smaller dogs tend to have longer lifespans than larger dogs, meaning that they age differently too and are probably a little more comparable to humans than large dogs. However, they still age quickly as puppies and slow down as adults.

You can consult this chart to get a better idea of how old your dog really is.

Size of Dog Small Medium Large
Age of Dog Age in Human Years Age in Human Years Age in Human Years
1 Year 15 15 15
2 24 24 24
3 28 28 28
4 32 32 32
5 36 36 36
6 40 42 45
7 44 47 50
8 48 51 55
9 52 56 61
10 56 60 66
11 60 65 72
12 64 69 77
13 68 74 82
14 72 78 88
15 76 83 93
16 80 87 120

Of course, this method isn’t nearly as easy to memorize. For a quick estimate of your dog’s age, it might not be a bad idea to stick with the seven-year method just to keep things simple. But for people who are truly curious about how old their dogs are in true dog time, this is a much more accurate system.

Another thing the team learned is that a dog’s average lifespan, when calculated in their own years, is about the same as a human’s. “The expected lifespan of labrador retrievers, 12 years, correctly translated to the worldwide lifetime expectancy of humans, 70 years,” the researchers wrote.

What do you think of this system? Is your dog as old as they seem? What’s your dog’s true age?

Check out the video below to learn more about the myth of dog years, including how the myth was created and perpetuated to begin with.

Why Adopt A Shelter Dog Month Should Be Celebrated Year Round: Click “Next” below!

Elizabeth Morey graduated summa cum laude from Aquinas College in Grand Rapids, MI, where she dual majored in English Literature and Spanish with minors in Writing and Business Administration. She was a member of the school's Insignis Honors Society and the president of the literary honors society Lambda Iota Tau.


Some of Elizabeth's special interests include Spanish and English linguistics, modern grammar and spelling, and journalism. She has been writing professionally for more than five years and specializes in health topics such as breast cancer, autism, diabetes, and Alzheimer's disease. Apart from her work at GreaterGood, she has also written art and culture articles for the Grand Rapids Magazine.


Elizabeth has lived in the beautiful Great Lakes State for most of her life but also loves to travel. She currently resides a short drive away from the dazzling shores of Lake Michigan with her beloved husband.

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