Dog years (or cat years) - a better estimation tool

06Apr 2013 by Charlie Nichols No Comments

Dog years, explained

Do you think one person year equals seven dog years. I did, until doing some research. I wanted to add a “fun” conversion factor for a conversion function in an Excel add-in I’ve created. What I learned is that the seven year equivalent value is a pretty poor approximation of a dog’s equivalent age. Dogs do mature more quickly than people, but when they are young they mature at an even faster rate (relative to people) than they do when they are older.

This post describes some capability you only get by installing an add-in for Excel. The add-in used here is fully functional and free during its trial period – so you’d have plenty of time to try this out. The add-in is called PowerUps for Excel and a link to download the free trial is at the bottom of the page.

The exact rate differs if you look at different sites but the consensus appears to be that the rate of maturation is much higher when dogs are young (first year) versus when they get older. I modeled this curve in the Excel add-in function I’ve written and charted the age in dog years relative to people years below. The values I based the function on are more of an average across the approximations I found on sites like WebMD,OnlineConversions.com, Wikipedia, Dogyears.com, etc. One other item to note is that the size of the dog matters too when estimating the equivalent age — larger dogs age at a faster rate than smaller dogs. I didn’t factor that into the function I created but some people reading this would be correct to point out that the size attribute matters too.

A similar approximation can be used to estimate the age of your cat. Essentially, the farther out you go, the more linear the estimation. In fact, if you run the conversion out to around 14 years or so you wind up with a factor of seven for the multiplier which may be where the 7 year generalization originates. Who knows? I don’t.

So, how old is your little Rufus or Sebastian?