Senior dog age calculator

When is a dog a senior? It depends on the breed's expected lifespan. Enter breed or size and age to see the current life stage and what to do in it.

Life stage
mature adult
  • Puppy
  • Young adult
  • Mature adult
  • Senior

Stages follow the 2019 AAHA Canine Life Stage Guidelines: senior begins in the last quarter of the breed's expected lifespan. Senior care guides.

The four life stages

  • Puppy: birth until growth finishes, 9 months for toys to 2 years for giants.
  • Young adult: from the end of growth to social and physical maturity, roughly the first third of life.
  • Mature adult: the middle years. Metabolism slows and breed-related disease begins to appear.
  • Senior: the last quarter of expected lifespan. The AAHA recommends exams every six months, because a year is a long time at this pace.

What to do in the senior stage, in detail: senior dog care guides.

Frequently asked questions

At what age is a dog considered a senior?

The AAHA guidelines define senior as the last 25% of the breed's expected lifespan. That is about 11 for toy breeds, 10 for small, 9 for medium, 8 for large and 6 to 7 for giant breeds. Individual breeds vary: a French Bulldog is a senior earlier than a Chihuahua of the same weight.

What changes when my dog becomes a senior?

Vet visits move to every six months with bloodwork, urine testing and blood pressure. Calorie needs drop about 20%, protein needs stay high, and joint pain, dental disease, kidney and heart disease become the things to watch for.

Is 7 years old for a dog?

For a Great Dane, yes: that is old age. For a Labrador it is the start of the mature-adult years, and for a Yorkshire Terrier it is mid-life. Size and breed set the clock, not the calendar.

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Sources

  1. Creevy KE, Grady J, Little SE, et al. 2019 AAHA Canine Life Stage Guidelines. Journal of the American Animal Hospital Association. 2019;55(6):267-290. www.aaha.org/resources/life-stage-canine-2019/
  2. American Veterinary Medical Association. Senior pets: how old is old? www.avma.org/resources-tools/pet-owners/petcare/senior-pets
  3. McMillan KM, Bielby J, Williams CL, Upjohn MM, Casey RA, Christley RM. Longevity of companion dog breeds: those at risk from early death. Scientific Reports. 2024;14:531. doi.org/10.1038/s41598-023-50458-w