You have definitely heard of the concept of “dog years” before. However, just in case you haven’t: the theory states that one year for your dog equates to seven years for a human being. The reason for this is that dogs mature quicker than we do. With this information, you may now be reaching out to quickly grab a calculator and see how old your dog is in human years. Not so fast though, because scientists have now determined that the old theory is not entirely correct, and it does not apply to all dog breeds.

Factors That Determine the Growth of a Dog

The two main factors here are the breed and the size of your dog. Interestingly, smaller dogs have longer lifespans than larger ones although they usually have a higher maturity rate in their younger years. To be clear, a small dog weighs less than 20 pounds, a medium dog is between 21 and 50 pounds, while anything beyond that is a large or giant dog.

Calculation of Dog Years

From one year old to five years, the rate of conversion from human to dog years is constant. One year old for any dog is actually 15 human years for a dog of any size, which is at least twice the seven years most people thought of before. Two dog years equate to 24 human years while three dog years are about 28 human years. Four and five dog years equate to 32 and 36 human years respectively. Imagine that!

Here is a helpful chart for determining your dog’s age.

One thing to keep in mind is that these are all educated speculations and might be different for some dogs. You may be wondering why there is a constant rate for all dog sizes up to five years. The reason is that most dogs mature quickly in their younger years. However, after that, aging slows down to differing rates for different dog sizes and that is where all the difference arises.