It’s often said that one dog year equals seven human years—but that’s an oversimplification. Veterinarians now say a dog’s first year is closer to 15 human years, with the second adding another nine, and each year after that about five. However, a dog’s size complicates things. Around age 6, large breeds begin aging more quickly than their smaller counterparts, and the gap grows more pronounced by age 8.
This aging disparity tied to body mass continues to puzzle researchers. While large mammals typically live longer than smaller ones, dogs defy that rule. In fact, for every 4.4 pounds of extra body weight, a dog’s life expectancy can drop by about a month. Theories suggest earlier onset of age-related illness in larger dogs or an increased risk of abnormal cell growth and cancer due to rapid development.
Regardless of cause, it’s a reality that dogs don’t live as long as humans. And while a new drug, conditionally approved by the FDA and in trials as of early 2025, may offer dogs a few more years, most owners will still likely outlive their pets. This is especially true for large breeds like Great Danes and Saint Bernards, which are beloved for their size but not for their longevity.
Using a 2024 Nature study of nearly 585,000 UK dogs across 155 breeds, researchers identified which dogs have the shortest average lifespans. The 35 shortest-living breeds recognized by the American Kennel Club were ranked. Popularity, based on the AKC’s 2025 data, was included but did not affect rankings. Read on to discover which breed lives just over five years, and which surprisingly small pups also made the list.
10 Shortest-Living Dog Breeds
10. French Bulldog
- Median lifespan: 9.8 years
- Popularity rank: 1
French bulldogs are favored in cities for their compact size and playful demeanor. With their expressive bat ears and flat faces, they charm owners everywhere, though health issues can limit their lifespan.
9. Bulldog
- Median lifespan: 9.8 years
- Popularity rank: 9
Bulldogs are brave and lovable, instantly recognizable by their iconic wrinkles and pushed-in snouts. Sadly, their unique build contributes to various health problems that often shorten their lives.
8. Saint Bernard
- Median lifespan: 9.3 years
- Popularity rank: 62
Known for their size and warmth, Saint Bernards have served both as rescue dogs in snowy mountains and as gentle family pets. Their immense size, however, leads to earlier aging and a shorter life.
7. Neapolitan Mastiff
- Median lifespan: 9.3 years
- Popularity rank: 128
Famous for their droopy jowls and ancient Roman heritage, Neapolitan Mastiffs are loyal and calm companions. These gentle giants are charming but don’t typically live beyond a decade due to their size.
6. Bloodhound
- Median lifespan: 9.3 years
- Popularity rank: 58
Bloodhounds, legendary for their sense of smell, excel in tracking people and objects. While their detective work is unmatched, they are prone to joint issues and don’t usually live very long.
5. Affenpinscher
- Median lifespan: 9.3 years
- Popularity rank: 162
The tiny but bold Affenpinscher features a monkey-like face and a spunky personality. Though small in size, these dogs often experience respiratory and neurological issues that can impact lifespan.
4. Mastiff
- Median lifespan: 9 years
- Popularity rank: 40
Mastiffs, with roots in medieval England, are protective and affectionate family pets. Despite their patient nature, their immense build tends to shorten their time with their human companions.
3. Cane Corso
- Median lifespan: 8.1 years
- Popularity rank: 14
The muscular Cane Corso hails from Italy and thrives on activity and training. Once war dogs, they’re now loyal pets, though their heavy frame and guarding instincts can mean shorter lifespans.
2. Presa Canario
- Median lifespan: 7.7 years
- Popularity rank: not available
Originally bred in the Canary Islands for farm work, the Presa Canario is a strong-willed breed. With proper handling, they make loyal pets, but their aggressive tendencies and size lower their longevity.
1. Caucasian Shepherd Dog
- Median lifespan: 5.4 years
- Popularity rank: not available
One of the shortest-living breeds, the Caucasian shepherd dog weighs over 100 pounds and serves as a fierce guardian. Their protective nature is admirable, but their massive build leads to a very brief lifespan.
Final Thoughts
Choosing a dog is a major decision—especially knowing some beloved breeds may only be around a few short years. While a pup’s lifespan shouldn’t be the only factor in your decision, being informed can help you prepare emotionally and financially. Always ensure your dog receives regular vet care, proper nutrition, and a loving home to maximize their time by your side.
FAQs
Q1: Why do larger dogs live shorter lives than small ones?
A1: Larger dogs age more quickly due to faster growth, increasing risk of age-related illness and cell abnormalities.
Q2: Can diet and exercise increase a dog’s lifespan?
A2: Yes, balanced nutrition and regular activity can improve a dog’s health and may help extend its lifespan slightly.
Q3: What is the new drug meant to extend dogs’ lives?
A3: As of 2025, a new drug conditionally approved by the FDA is in clinical trials, aiming to add a few years to dogs’ lifespans.
Q4: Should lifespan affect which dog breed I choose?
A4: Lifespan is worth considering but should be balanced with lifestyle, experience, and commitment to the dog’s needs.
