10 years 56 years
14 years 72 years
18 years 88-91 years *
20 years 91-96 years*
21 years 96-106 years*
*sources differ on the later years
Age of Dog/Cat Human years
3 months 5 years This chart is based on tooth
and bone growth, sexual
6 months 10 years maturity and other factors
related to maturity, it is not
1 year 15 years exact but is a fairly
accurate comparison.
2 years 24 years Larger breeds of dogs have a
shorter life span and smaller
4 years 32 years dogs have a longer one but
a small dog may mature more
6 years 40 years quickly in the first few years
and a large dog more slowly.
8 years 48 years
10 years 56 years
14 years 72 years
18 years 88-91 years *
20 years 91-96 years*
21 years 96-106 years*
*sources differ on the later years
<--Return to Dr Sue's Home Page, or go to