It turns out that there may be a better way of converting a dog’s age to that of a human. The typical formula simply scales the dogs age by 7 to adjust for the typical life expectancy of each species. A new method published in Science adjusts the dog’s “virtual age” according to the relative rates of DNA methylation.

Certain genes that are shared by dogs and humans accumulate methyl groups at similar rates. This fact allows a more accurate conversion between the ages of species. Turns out that it’s just slightly more complicated: