Wednesday, May 26, 2010

How Old is That Dog?

From Eldredge, Debra M., et al., 2007 Dog Owner's Home Veterinary Handbook, 4th edition. Howell Book House, Hoboken, New Jersey.

Dog years:       Human Years (for a 21-50 lb. dog)
       5                                37
       6                                42
       7                                47
       8                                51
       9                                56
       10                              60
       15                               83
       16                               87
       17                              92
        18                             96
        19                             101
       20                              105

I didn't reproduce the entire table (it's Appendix B), but as you can see, it's not a straightforward 1 dog year = 7 human years. For smaller dogs (think Mr. D!), it's a smaller conversion factor (e.g., a 5-year-old dog less than 20 lbs is about 36 human years); for a big dog, it's a larger factor (over 90 lbs., a 5 year old dog is the equivalent of 42 human years).

So, trying to accommodate the conversion factor slowing as the dogs age made me hazard that at 40, Belle would be about 180 human years. Give or take a decade (this is where I wink at you).

This means Stinkerbelle is about 56 human years right now, and Mr. Big, who has lost 8-10 lbs. since he started his diet last fall, is 66 in human years.

And I am, in canine years, 6 (if I was a 51-90 lb dog). Hooray!!!


  1. Although I'm thrilled you'd reference one of my books to put me in my place, common knowledge is 7 dog years for every 1 person year. I'm still standing by my 280.
    I'm 49 years old and for 49 years it's been 7 to 1.


    Explains where the 7:1 came from and why it doesn't work well. Since I want my pups with me as long as possible, I'm relieved that they're younger than an age obtained with the 7:1 ratio that's mistakenly used. It also means I have to watch for age-related changes at different times than I thought, or behavior issues at earlier/later times. I didn't realize that 'common knowledge' of 7:1 had changed till I got the pup, but since change and learning are good things, I'm happy to learn something new. And since I've found over the years that 'common knowledge' and 'conventional wisdom' are often way off...

    Sorry you're offended. I wasn't by the implication I can't multiply.