Dog Years: How Do You Calculate Dog Years to Human Years - Animal Facts

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Since the 1950s, the popular calculation of how old a dog is “in human years” has

been that 1 dog year is the equivalent of 7 human years.

It’s a popular myth that refuses to give up the ghost.

But, because dogs mature at a different rate than humans, it’s not so straightforward.

Age is more than just a chronological measurement of years lived.

It’s also an expression of how our bodies have been affected by the passage of time.

As a general guideline, the American Veterinary Medical Association breaks down a dog’s

age comparison like this:

15 human years equals the first year of a medium-sized dog’s life.

Year two for a dog equals about nine years for a human.

And after that, each human year would be approximately five years for a dog.

Let’s find out what each stage is and why.

Let’s get started.

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If your dog is 1 year old, he’s roughly the equivalent in physical and mental maturity

as a 15-year-old human.

As we saw in our last video, large breeds tend to mature faster and live shorter lives

than smaller breeds, so for the sake of this discussion, we’re going to focus on medium

sized dogs.

At this age, the dog may look like a full-grown adult dog, but he still has some growing to

do, both physically (albeit not much) and mentally.

He’s still quite playful in a puppy-like manner and he’ll probably put on a bit more

weight and muscle mass in the next few months.

The average age a dog reaches adulthood is about 15 months.

When your dog reaches 2 years old, he’s roughly the equivalent of a 24-year-old human.

He’s reached both mental and physical maturity, but still young enough to stay out all night

partying with his buddies… oh, wait… no that’s humans…

About 9 human years have passed for him.

Plenty of time to get that college degree.

After year two, things start to slow down for your four-legged family member.

Each of the following years sees him aging about the same as a human does in 5 years.

Your 3-year-old buddy is approximately 29 human years.

However, this is the time when larger dogs are at a distinct disadvantage to smaller

dogs, especially going into years 7-9 depending on the breed.

At this age, a Great Dane is near the end of life where a Chihuahua or Bichon Frise

has several years to go.

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