At what age is my dog considered a senior? - Prestige Animal Hospital
As we all know, dogs can vary from tiny little toy breeds to the giant Great Danes and Saint Bernard breeds. So really, the larger breeds tend to have a shorter life span in general. A giant breed dog may have a life span of eight to 10 years, so five years old is considered more senior. Whereas a smaller dog who has a lifespan of 14 to 16, it might be around the seven to the nine-year range that they become a senior. So it depends on what size and type of breed of dog you have.