Friday, May 18, 2012
   
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Dog vs Human Ages

The common unit of measure to compare dog years to human years is:

1 human year = 7 dog years

Different breeds of dogs age at vastly different rates so this rule of thumb only goes so far. Giant dogs like Great Danes and St. Bernards may have a life expectancy of under 10 years.  Chihuahuas might still be going strong at 15.  You can think of some dogs as either aging faster or simply not living as long as others.  In any case, a life that is significantly shorter than the average human life is one of the difficulties that dog lovers face. 

Alternatively, since dogs reach maturity in about 1 year, that could be seen as 16 in human terms.  Then add about 7, 5 or 4 years for every year your dog ages depending on the size of your dog.

Giant breeds examples: Great Danes, Mastiffs
Large breeds: Retrievers, Collies
Small breeds: Chihuahuas, Pomeranians

A 5 year old giant breed dog would then be:
(5-1) x 7 +16 = 44 in human terms

A 5 year old large breed dog would then be:
(5-1) x 5 + 16 = 36 in human terms

A 5 year old small breed dog would then be:
(5-1) x 4 + 16 = 32 in human terms

Human equivalent years
Dog
Years
Giant
Breed
Large
Breed
Small
Breed
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
16
23
30
37
44
51
58
65
72
79
86
93
100
16
21
26
31
36
41
46
51
56
61
66
71
76
81
86
91
96
101
16
20
24
28
32
36
40
44
48
52
56
60
64
68
72
76
80
84
88
92
96
100
Specific breeds such as Border Collies and Bulldogs can have shorter life expectancies than their size would suggest.  This could be because Border Collies lead hyper active lives and Bulldogs are essentially dwarfed Mastiffs and share the shorter lives of their ancestors. Beyond genetics, good nutrition, daily exercise, medical care, a warm family environment and an interesting life all serve to increase the lifespan of your dog.  Note that the average lifespan of a dog in the US has doubled in the last several decades.  The basic dog hasn't changed as much but the care of dogs has changed dramatically for the better.