The answer to this question isn’t as easy as it once was. We used to say a standard seven human years for every dog year. Now, we know that different sizes of dogs age differently. Smaller breed dogs frequently live longer lives, so a year of their life is less human years than a large or giant breed dog. So, let’s break it down:

  • At a year, all dogs except giant breed dogs are considered to be around 15 years of age…giant breed dogs are considered to be around 12 years of age.
  • At 5 years of age, all breeds except giants are roughly 36 human years old, giant breed dogs are considered to be around 45.
  • At 10 years of age, small breed dogs are 56, medium dogs are 60, large breed dogs are 66 and giant breed dogs are 79.
  • Finally, at 15 years of age, small breed dogs are considered to be 76 human years, medium-sized are 83, large breeds are 93, giant breeds are 114 human years!

Cats, we can still roughly say that the first year of life is equal to 15 years of a human, the second year adds nine years, and each year of their life after equals four human years. So, a 10-year-old cat is roughly 56 human years!

We covered this and why it is important to know if your pet is a senior in the episode Is My Pet a Senior and Why Does it Matter on the Senior Pet Podcast listen now!

– Dr. B