My dog is getting older but when would he be considered senior?

I know that 1 human year equates to 7 seven dog years.

  • My dogs 8 which I think is oldish? But we/he still play frisbee like he's 2 & he's got osteoarthritis in 1 elbow from over doing it but he's fit as a fiddle. Look after them & they'll live an age. Compare to humans it's, like the queen & royal family. No worries they all get well older than average wage jimmy who's had a hard life. Play play & never work unless your a fool or a horse
    – stew
    Commented Jun 13, 2017 at 4:00
  • 1
    No, you THINK you know that 1 human year equates to "7 seven dog years".
    – sleddog
    Commented Jun 13, 2017 at 12:41
  • @sleddog This question is almost four years old now, the answers already addressed that point...
    – Timtech
    Commented Jun 13, 2017 at 21:33
  • 1
    @Timtech Then why haven't you selected the most appropriate answer yet? :^)
    – sleddog
    Commented Jun 14, 2017 at 12:30

3 Answers 3


When is a human considered to be old? The answer really depends on the individual.

The seven year rule is old and inaccurate. There are several other methods that take the life expectancy of dogs into account better, eg one dog-year equals five humans-years for small dogs and seven for bigger dogs. And then there are even some nonlinear metrics in determining a comparable age value.

If you and your dog think that he is old, ie he behaves like an old dog, treat him as such. I don't think it is good to treat a juvenile and active dog of high age as if he was a broken senile. Of course you still have to be careful as older dogs, no matter how active they are, will still have age-related problems and are more prone to injury than younger dogs.

  • To back you up, at 7 months a dog is concidered to be 18 years old according to the vets' booklet.
    – Salketer
    Commented Oct 9, 2013 at 11:59
  • 1
    @Salketer good point. At first I wanted to disagree as I consider dogs around 9 month to be in puberty (more like 15 or 16). But then I realized that it might be useful to distinguish the development of a dogs body and the dogs behavior when talking about its age.
    – Baarn
    Commented Oct 9, 2013 at 12:11
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    Totaly, the former 7-year-rule was mostly used to imagine the age of the body. Trying to find a "rule" that would fit both mental and physical traits at certain age is useless.
    – Salketer
    Commented Oct 9, 2013 at 13:02

8 years, would be a good average to concider your dog as "old" or "senior" but there are no real fixed age. Just the difference between the races' lifespan makes it easy to understand. Small dogs tend to live between 15 to 20 years as big dogs will live between 12 to 15.

The reasons why I say 8 years old is the threshold is because that at about this age that dark dogs will start having gray hair. At that age, the dog's diet should be changed a bit and the adult food should be changed to senior food as per your dog's favorite brand will most likely point out.


It varies, but cats and small dogs are generally considered to be old at the age of 7. Larger breed dogs tend to have shorter life spans and are considered to be old when they are approximately 6 years of age.

Owners tend to want to think of their pet's age in human terms.

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