A Straight Dope Classic from Cecil's Storehouse of Human Knowledge

Is it true that one "dog year" equals seven "human years"?

June 13, 1986

Dear Cecil:

Every year we hear the Alpo man claim his 14-year-old dog is actually 98 years old in human years. Yet I remember reading in some journal that the seven-years-for-every-one-dog-year rule is only applicable to dogs under 10 years old. After a certain age the conversion factor reduces considerably, so that a 98-year-old Alpo dog is really in his mid-70s. I need the Straight Dope so I can get the candles right for my hound.

Cecil replies:

I've seen various formulations for this over the years. One of the simplest and most sensible goes like this: The first year of canine life is equal to 21 years of human life — in other words, the puppy grows to adulthood. Every additional dog year is equivalent to four human years. Thus a 10-year-old mutt is the equivalent of 57 human years old (9 x 4 + 21). Likewise, the Alpo dog is not 98 (14 x 7) but 73 in human terms (13 x 4 + 21).

The formula jibes reasonably well with the known landmarks of canine life. Dogs reach middle age when they're 6 or 7, which works out to 41-45 in HY. Life expectancy for most is 12-15 years (65-77 HY); occasionally one manages to creak along until age 20 (97 HY). That makes a lot more sense than saying a 20-year-old dog is 140, and it sure saves on the candles, too.

Related Posts with Thumbnails

Recent Additions:

A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
By Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams
A Straight Dope Classic by Cecil Adams

Send questions for Cecil Adams to: cecil@chicagoreader.com

Send comments about this website to: webmaster@straightdope.com

Terms of Use / Privacy Policy

Advertise on the Straight Dope! Your direct line to thou- sands of the smartest, hippest people on the planet, plus a few total dipsticks.

Publishers - interested in subscribing to the Straight Dope? Write to: sdsubscriptions@chicagoreader.com.

Copyright © 2014 Sun-Times Media, LLC.