There Is a More Accurate Way of Calculating a Dog’s Years.
If you’ve ever multiplied your puppy’s age by 7 to get an idea of how old he really is or how young he is, you’ve probably noticed that the formula has its drawbacks. The new calculation is a little more difficult to remember, but it gives a more accurate answer.
To come up with a new formula, the researchers compared Labrador DNA methylation to DNA from people of different ages. Methylation is a biochemical process that occurs with DNA as we age; the older we get, the more methyl groups in our DNA.
According to non-peer reviewed research , you can plug your dog’s age into this formula to get roughly the equivalent human age:
31 + (16 * ln (AGE))
Copy and paste this formula into your Google search bar, replace “AGE” with your dog’s age and you will get your answer. The “Ln” in the formula refers to the natural logarithm function that Google and most mid-size calculators know. (This is one of those extra buttons you’ll see on your iOS calculator if you turn your phone to the side.)
This is how it looks for Labradors of different ages:
- 1 actual year: 31
- 2 actual years: 42
- 3 actual years: 49
- 4 actual years: 53
- 5 actual years: 57
- 6 actual years: 60
- 7 actual years: 62
- 8 actual years: 64
- 9 actual years: 66
- 10 actual years: 68
- 11 actual years: 69
- 12 actual years: 71
- 13 actual years: 72
- 14 actual years: 73
- 15 actual years: 74
This makes a little more sense than the seven-year-old rule: your puppy looks like an adult by the time it reaches its first birthday, becomes average over the next few years, and transitions into seniors’ territory around the age of 9.
Even if other scientists end up liking this formula, it has its limitations. Different dogs age at different rates and this has only been calibrated for one breed. For example, some terriers live to be 15–20 years old, while giant breeds such as Great Danes can live to be 8 years old. Besides DNA methylation, there are other ways to think about aging. For example, how physically and mentally mature is your growing puppy? This is a more difficult question.