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Name: Mary
Status: Other
Age: 50s
Date: 2/15/2004

I would like to know how many year's equal one year of a
Cat's life compared to a dog's life.. I heard a dog has 7 year's to
year of a human.. Is this true.. So I would like to know how a Cat
compares to dog year's


The way that dogs and cats mature doesn't correspond exactly to the way
that humans do. Dogs and cats grow up very quickly during the first two
years of life and then mature more slowly after that. Large dogs tend to
have shorter lifespans than small dogs. Cats tend to live longer than

A nice chart, developed by Dr. William Fortney at Kansas State
University's College of Veterinary Medicine, is shown on the website of
the Central Dakota Humane Society website
( There are also calculators on the
web that will estimate your dog's age, but most of these don't account
for size.

A similar chart for cats can be found at

Purina has recently sponsored a site where you can enter information
about your dog's health, breed, weight and behavior to see if these are
likely to affect it's lifespan. It is based on the methods used to see
how diet, exercise, smoking, etc. affect human lifespan predictions.

Laura Hungerford, DVM, MPH, PhD
University of Maryland, School of Medicine

Click here to return to the Veterinary Topics Archive

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