This equation provides the "doggie age" category,  the categorical animal equivalent of human physical maturity for cats and dogs in varying weight ranges. 

The doggie age categories are listed as:

Feline (for all cats):

• kitten
• adult
• senior
• geriatric

Dogs (for dogs in weight categories); the "doggie age" category varies both by a dog's chronological age and the animal's weight

• puppy
• adult
• senior
• geriatric

Description

The doggie age is the pet equivalent of the animal's lifestyle and health equivalent age compared to normal human years.  In other words this is a gauge of the dogs predicted health and lifestyle based on how old they chronologically are.  This is the fundamentally based on the rule-of-thumb that "a year for a dog is like seven years for a human".  This equation takes into account the weight category of the dogs because larger dogs age faster. 

As you'll see in the data set, the dogs in the largest weight category most likely do not ever reach 19 or 20 years of age.  And a dog who is greater than 90 pounds and who reaches the chronological age of 18 years is feeling like a human who is 139 years old.  That is, the doggie age of a dog that was born 18 years ago are 139 years.

Example

My golden retriever, Brutus, is about 12-1/2 years old and at this writing weighs about 55 lbs.  So, he falls in the lower end of the 50-90 pound weight (mass) range and is reported  by the underlying data  to be 77 in doggie years.  And this equation reports this doggie age puts him in the doggie age category: geriatric.

He has in just the past approximately year and a half started exhibiting real signs of age.  Stiffness in the joins and a few other symptoms which also correlates closely with the transition the Doggie years data set shows from senior to geriatric.  Its a sad thing when your friend of so many years starts to really show aging symptoms and this data set appears to correlate well to at least my one example.

We would most appreciate if you would compare your own dog's experience  to the equation and provide comments at the bottom of this page.

See also

• Doggie years [data set]
• Doggie Years Eq