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Your pet may seem young at heart, but his age may tell a different story. While U.S. pet parents are technically considered senior citizens at 65, senior status in pets isn’t absolute. Whether your pet is ready for his “AARF” card or not has a lot more to do with his species, breed and size than with his actual age.


For mammals, large body size is often a good predictor of a long life — the average life span of a blue whale is 80 to 90 years, for instance. Unfortunately for four-legged family members, this size rule does not apply. Large breed dogs generally have shorter lifespans than smaller canines — scientists think they simply age faster than petite pups.


Breed can also impact your pet’s life span. For example, Boxers have a shorter life span than other breeds of the same size due to genetics, and Siamese cats and Standard Poodles live longer than similarly sized breeds!


Though there are exceptions to every rule, you can generally consider your dog eligible for senior status at:


  • 6 years old for giant breeds (over 90 lbs)
  • 7 years old for large breeds (51-90 lbs)
  • 8 years old for medium breeds (21-50 lbs)
  • 9 years old for small dogs (under 20 lbs)


The rules for cats are less complicated (for once!). The American Association of Feline Practitioners. considers cats aged 7 to 10 years to be middle-aged, and 11 to 14+ senior.