Dog lifespan guide
How long do dogs live?
Reviewed: 2026-09-08 · Model: dog-lifespan-v0.1
Direct answer
The mixed-dog baseline in dog-lifespan-v0.1 is 12.0 years, with a broad starting range around 9.5 to 15.0 years before age, size, breed, body condition, and health adjustments.
Size matters more for dogs
Dog lifespan varies strongly by adult size. Toy and small dogs often have longer population-level lifespan than large and giant dogs, so PetLifeYears keeps dog size as a core model input.
Factors that change the estimate
The dog model combines current age, adult size, breed baseline, sex, neuter status, body condition, activity, and known health history.
- Toy dogs start from a 14.2-year size baseline in dog-lifespan-v0.1.
- Large dogs start from a 10.8-year size baseline, and giant dogs from 8.8 years.
- Country is stored for US, UK, Canada, Australia, China, Singapore, and Japan context, but dog-lifespan-v0.1 does not adjust numbers by country yet.
Use the calculator for a personalized educational range based on age, adult size, body condition, and health context.
Related guides
Sources and limits
Lifespan numbers on this page are traced to the listed source set or the versioned PetLifeYears model. They are educational planning ranges and do not replace veterinary advice.
- Frontiers in Veterinary Science / PMC: Life expectancy tables for dogs and cats derived from clinical data
- Scientific Reports: Life tables of annual life expectancy and mortality for companion dogs in the United Kingdom
- Companion Animal Health and Genetics / PMC: Lifespan of companion dogs seen in three independent primary care veterinary clinics in the United States
- Aging / PMC: Birth mass is the key to understanding the negative correlation between lifespan and body size in dogs
- American Animal Hospital Association: 2019 AAHA Canine Life Stage Guidelines