How old is your dog in “human” years?

We used to just assume that a “dog year” equaled seven human years and estimate our dogs’ human-age-equivalent with a simple multiplication. Cali is 7 1/2 years old (calendar years) so she’s  … roughly my age in human years. (She still has a lot more fun though.)

Turns out that that doesn’t work.

Sometime last year, I first saw a chart that estimates dogs’ ages with adjustments for smaller- and larger-breed dogs since smaller dogs tend to live longer. Cali’s vet has this chart hanging on the wall, and I have seen it several places online. Essentially, in a dog’s first calendar year, she matures about as much as a human does during her first fifteen years. Then in year two, while your human offspring is a terrible two, your dog becomes almost civilized — roughly as mature as a 24-year-old human adult.

Guess what? According to this chart, Cali’s human-age equivalent is … drum roll … roughly the same as my age. And exactly the same as the old “7 years” trick.

But … yeah, that one doesn’t work anymore either.

Now we’ve got a shiny new method of calculating dogs’ ages. All you need is an advanced degree in mathematics …

Seriously. According to the Washington Post, all you have to do is “Multiply the natural logarithm of the dog’s age by 16, then add 31.”

Easy-peasy. Wait, what’s a natural logarithm??

Wikipedia to the rescue: “The natural logarithm of a number is its logarithm to the base of the mathematical constant e, where e is an irrational and transcendental number approximately equal to 2.718281828459.”

Or … not.

I have no idea what Cali’s age-equivalent would be with this formula. I’m going to just pretend it’s something like 25. And holding.