With hundreds of different breeds, dogs are the most genetically diverse species of mammal on the planet. This leads to differences we all recognize — size, coloring, and personality, to name a few. Another key difference between dog breeds is their average lifespan. So, how long do dogs live? The typical "dog years" equation of seven years equalling one human year isn't really applicable since a dog's life expectancy can vary greatly.
Generally speaking, small dogs have longer lives than large dogs. For example, a Chihuahua will almost always outlive a Great Dane just like a Dachshund will usually outlive an Irish Wolfhound. While scientists are still studying the precise mechanisms of dog aging, one thing is clear: a dog's size and growth rate is inversely proportional to the dog's lifespan.
In this guide, we'll discuss the life expectancy of different dog breeds and delve into what makes different dog breeds age differently.
How Long Do Small Dog Breeds Live?
Small dogs, like terriers and toy poodles, can be expected to have relatively long lives compared with larger dogs. These dogs can easily live into their teens if well cared for, with a lifespan of at least 15 to 16 years being common. Almost all of the longest living dog breeds are small. Below are the average lifespans of several popular breeds of small dogs.
- Maltese: 12+ years
- Miniature Schnauzer: 12+ years
- Pomeranian: 12+ years
- Shih Tzu: 13+ years
- Jack Russell Terrier: 14+ years
- Toy Poodle: 14+ years
- Yorkshire Terrier: 14+ years
- Pug: 15+ years
- Chihuahua: 15+ years
Please note that these are averages. Numerous factors can increase or decrease a dog's lifespan, such as exposure to diseases and diet. (More on those factors later.)
How Long Do Medium to Large Dog Breeds Live?
Many medium or large dog breeds can be expected to live relatively long lives, sometimes as long as small breeds. Because there can be significant size variation within breeds, animals within the same breed can be medium or large. The American Kennel Club has no set weight for German Shepherds, for example.
As an interesting note, the longest-lived dog on record was an Australian cattle dog named Bluey who lived to 29 years, 5 months. Generally speaking, medium-sized dogs live 10-13 years, though there are notable exceptions due to congenital health problems as in bulldogs. Below are some average life expectancies of medium to large dog breeds.
- Bulldog: 7+ years
- Old English Sheepdog: 10+ years
- Greyhound: 10+ years
- German Shepherd: 10+ years
- Rottweiler: 10+ years
- Boxer: 10+ years
- Samoyed: 11+ years
- Labrador Retriever: 12+ years
- Golden Retriever: 12+ years
- Cocker Spaniel: 12+ years
- German Shorthaired Pointer: 12+ years
- Irish Setter: 12+ years
- Shiba Inu: 12+ years
- Border Collie: 13+ years
- Beagle: 13+ years
- Springer Spaniel: 13+ years
- Australian Shepherd: 13+ years
- Siberian Husky: 13+ years
- Dalmatian: 13+ years
How Long Do Giant Breeds Live?
Giant breeds live the shortest lives of all dogs. Many have expected lifespans in the single digits. Generally, these dogs are 90+ pounds. Below are some expected life spans for giant dog breeds.
- Great Dane: 6+ years
- English Mastiff: 6+ years
- Irish Wolfhound: 6+ years
- Bernese Mountain Dog: 6+ years
- Bull Mastiff: 7+ years
- St. Bernard: 8+ years
- Newfoundland: 8+ years
- Cane Corso: 10+ years
- Great Pyrenees: 10+ years
- Doberman: 10+ years
Why Does Size Affect How Long a Dog Lives?
There's a clear correlation between dog size and average lifespan — but why is this? A study published in 2013 in The American Naturalist attempted to answer the question with enlightening results.
Essentially, they found three mechanisms of aging related to size: an increased rate of aging, higher early mortality, and an overall higher baseline mortality. One way to look at it is that very large dogs have cashed in their evolutionary chips for size rather than long life.
As the study explains:
"Organisms cannot allocate unlimited resources to growth, maintenance (repair), and reproduction throughout life. Trade-offs between these traits are inevitable. Although large size can increase short-term survival and fecundity, growing large rapidly and maintaining a large body size might come at the cost of reduced survival later in life. There is considerable evidence that growing fast can compromise an individual's lifespan."
The most significant finding of the study was that larger dogs experienced an increased aging rate than smaller dogs. So, those dog years you keep hearing about? They mean something different for big dogs than they do for smaller dogs.
For some interesting specifics, the researchers found that an increase of two kilograms (4.4 pounds) among breeds decreased a dog's life expectancy by one month. Additionally, size accounted for 38-49% of the difference between dogs' relative aging rates, which measured how far along a dog was in its lifespan rather than simply years and months.
Interestingly, the study did not find a correlation between breed size and increased senescence (i.e., the natural physical and mental deterioration that comes with age). As such, even though larger breeds generally die younger, they can't be considered geriatric for as long as a dog who lives a very long life.
How Long Do Dogs Live? It's a Matter of Evolution
It's important to recall two things: First, evolution does not care about an individual's overall lifespan — rather, it cares about an individual's ability to reproduce. A dog who survives to six years old and produces the same number of puppies as a dog that survived to 15 is considered equally successful by evolution.
Second, humans have long steered dogs’ evolution, so artificial selection for traits — including size — has replaced natural selection in many ways. Genetically, a dog's value is often determined by its usefulness to humans for a specific task — like herding sheep, hunting rats, or being a family companion.
What about mutts, though? Dogs who have not been purpose-bred or are genetic mongrels (not a bad word, by the way) generally live 10-13 years — though that largely depends on their genetic stock, and can vary widely. Due to their mixed heritage, these dogs often avoid many genetic problems that plague over-bred species like German Shepherds. As such, mixed-breed dogs may live longer than similarly-sized purebred dogs.
How to Care for Aging Dogs
Just like people, dogs get old and start to experience health problems. These can come in the form of hip and joint discomfort, tooth and gum problems, digestive issues, and more. Veterinarians recommend beginning geriatric checkups of small dogs at around age 11, medium or large dogs at age 9 or 10, and very large dogs as early as 6 or 7. Besides medical checkups, medicine, and procedures, there are some things dog owners can do regularly to help their dog stay healthy into their later years.
Getting your dog adequate exercise is one way to help them age well. Another is ensuring a nutritious diet, which can be supplemented just as a human's can. Hemp oil, for example, can help a dog maintain healthy joints, bones, nails, teeth, and fur. Glucosamine is widely admired for its health benefits in humans, and the same applies to dogs; this can also be said for omega-3 fatty acids. Giving your senior dog health-boosting treats may help support normal inflammatory responses and help with discomfort, helping your furry companion stay happy well into their older years.
One thing that won't change is the unique bond humans have with dogs — they're our genetic allies. We've co-evolved with them, and we love each other for it. While it's inevitable that dogs age faster than people, we can help them be happy and comfortable well into their golden years. They'd do the same for us, after all.