Dog Life Expectancy Calculator: How Long Will My Dog Live?

How it works

Breed median lifespan m from McMillan et al. (2024) · lifespans spread as a normal curve with SD = 20% of m · chance of reaching age t = Q((t − m) ÷ SD), where Q is the upper-tail normal probability · expected lifespan for a dog alive at age a = the age t where Q((t − m) ÷ SD) = ½ × Q((a − m) ÷ SD) · years remaining = expected lifespan − a · mixed breeds by weight: straight line between the size-group medians at 15, 40, 70 and 120 lb

The starting point is the median lifespan of each breed from the largest study of its kind: McMillan and colleagues (2024) analysed records of 584,734 dogs in the UK, of which 284,734 had died, across more than 150 breeds. Smaller breeds and breeds with longer muzzles lived longest (the Lancashire Heeler and Tibetan Spaniel past 15 years), while giant and flat-faced breeds had the shortest lives (the French Bulldog and Bulldog at 9.8 years, the Cane Corso at 8.1). For a mixed breed, choose the weight option: the calculator takes the median of the breed medians in its size group (small, medium, large or giant) and draws a straight line between them by adult weight. The crossbreed option uses the study’s overall crossbreed median of 12.0 years. A breed median tells you about newborn puppies, but an older dog has already survived the early risks. So the calculator treats lifespans as a bell curve around the median, with a spread of 20% of it (about 2.6 years for a Labrador), and works out the median age of death among dogs that are still alive at your dog’s age. That is why an 8-year-old Labrador’s expected lifespan is a little above the breed median, and why the years remaining never drop to zero. The table and chart show the chance of reaching each birthday from today. The dog age calculators on this site convert dog years to human years; this one estimates how long your dog is likely to live.

Worked example

An 8-year-old Labrador Retriever has a breed median lifespan of 13.1 years. With a spread of 20% × 13.1 = 2.62 years, the chance that a Labrador reaches 8 is 97.4%. Among Labradors still alive at 8, half reach 13.2 years, so the expected lifespan is 13.2 years and about 5 years 2 months remain. The middle half of these dogs would die between about 11.5 and 14.9 years, and the chance of reaching age 14 from today is about 38%.

Sources: Wikipedia: Aging in dogs (breed life expectancy table from McMillan et al. 2024, Scientific Reports 14:531) · SimpleDecisionMaker: Dog life expectancy calculator (VetCompass and Kealy 2002 lean-feeding figures) · Omni Calculator: Dog life expectancy calculator

Frequently asked questions