How long do dogs live on average?

12.5 years is the median across 584,734 UK dogs (McMillan et al., 2024) — meaning half lived longer. Purebreds came in at 12.7 and crossbreeds at 12.0. Females outlived males, 12.7 to 12.4. But an overall average is close to useless for your dog, because the spread between breeds runs from 5.4 years to 15.4.

Which dog breed lives the longest?

Lancashire Heeler, at a median of 15.4 years, followed by Tibetan Spaniel (15.2), Bolognese (14.9) and Shiba Inu (14.6). At the other end: Caucasian Shepherd Dog (5.4), Presa Canario (7.7), Cane Corso (8.1) and Mastiff (9.0). Two familiar breeds sit lower than people expect — Bulldog and French Bulldog both at 9.8.

Do big dogs really have shorter lives?

Yes, but far less than you've been told. Median lifespan was 12.7 years for small breeds, 12.5 for medium and 11.9 for large — a spread of about ten months. Compare that to the ten-year spread between breeds. Size is a real effect and a weak one; the popular dog-age charts that imply large dogs age roughly 60% faster are overstating it by a wide margin.

What shortens a dog's life more than size?

A flat face. Brachycephalic breeds had a median of 11.2 years against 12.8 for medium-muzzled ones — a 1.6-year gap, twice the entire small-to-large size difference. Medium-sized flat-faced breeds showed a 2.69-fold faster time to death than small long-muzzled ones (9.4 years versus 13.3). If you're choosing a puppy and you care about years together, face shape deserves more of your attention than weight.

Do long-nosed dogs live longest?

No — and this is the trap. Long-muzzled (dolichocephalic) breeds came in at 12.1 years, behind medium-muzzled at 12.8. The widely-repeated "small long-nosed dogs live longest" line comes from a specific combination — small and long-muzzled breeds reach 13.3 — not from long muzzles winning on their own. It's the difference between a main effect and an interaction, and it's easy to get backwards. We nearly did.

Do crossbreeds live longer than purebreds?

In this study, no — the opposite. Crossbreeds had a median of 12.0 years versus 12.7 for purebreds. That cuts against the common "hybrid vigour" assumption. One honest caveat: crossbreeds are a mixed bag by definition, and the study notes it can't assign them a size or muzzle category, so some of that gap may reflect what's in the mix rather than crossbreeding itself.

How reliable are these numbers?

They're the best available, with real limits worth knowing. The source is McMillan et al. (2024), Scientific Reports — 584,734 dogs, 155 breeds, peer-reviewed, with confidence intervals, released CC BY 4.0. The limits: it's a UK population drawn from rehoming, insurance and vet-corporate records, so a dog has to enter those datasets to be counted, which likely under-counts dogs that die very young. And some breeds rest on few dogs — the Caucasian Shepherd's 5.4 years comes from just 52 of them.

How Long Do Dogs Live? Median Lifespan for 155 Breeds

Across 584,734 UK dogs the median was 12.5 years. But that single number hides a ten-year spread between breeds — and the thing most people ask about, size, turns out to be nearly the weakest signal in the data.

Last reviewed 2026-07-17 · Sources listed in methodology

The short answer is 12.5 years. That's the median across 584,734 UK dogs in McMillan et al. (2024), the largest study of dog longevity yet published — half lived longer than that, half didn't.

The short answer is also nearly useless, and it's worth understanding why before you take any comfort or alarm from it.

The number that actually matters is your breed's

Group those 584,734 dogs by size and the medians barely move. Group them by breed and they span a decade:

Grouped by…	Range of medians	Spread
Size (small → large)	12.7 → 11.9 years	0.8 years
Muzzle (medium → flat)	12.8 → 11.2 years	1.6 years
Breed (Lancashire Heeler → Caucasian Shepherd)	15.4 → 5.4 years	10 years

Ten years versus ten months. Size is a lossy compression of breed — it throws away almost everything that matters and keeps a sliver. Which is awkward, because "small, medium or large?" is the question nearly every dog age calculator asks, including the ones that then tell you how fast your dog is ageing.

Every breed in the study

Here's the full table — all 155 breeds, each with its measured median, the study's confidence interval, its hazard ratio against the average, and how many dogs it rests on. It's reproduced from the paper's supplementary data under CC BY 4.0. Sort or filter it as you like.

		95% CI

Median lifespan is the age by which half the dogs of that breed had died. Risk vs average is the study's hazard ratio against all breeds — below 1.0 means longer-lived than typical. Crossbreeds: 12.0 years (reported separately; size and muzzle data exist for purebreds only). Thirteen breeds have no upper confidence bound because too few were recorded — shown as "no upper bound" rather than filled in. Miniature Dachshund is listed at 14.0, the figure in the paper's data table; its Fig. 3 caption says 12.2, and we explain that on our methodology page. Data: McMillan et al. (2024), Scientific Reports 14:531, CC BY 4.0. UK population.

What the extremes have in common

Read the bottom of that table and a pattern jumps out. Caucasian Shepherd Dog, Presa Canario, Cane Corso, Mastiff, Neapolitan Mastiff, St Bernard — the shortest-lived breeds are almost all giant guardian breeds. That's the size effect, but concentrated at an extreme the small/medium/large buckets can't see: these dogs aren't "large", they're enormous, and the study's "large" category lumps them in with Labradors.

The top of the table is more interesting, because it isn't just "small dogs". Lancashire Heeler, Tibetan Spaniel, Shiba Inu, Papillon, Border Terrier — all small, yes, but plenty of small breeds sit mid-table. And the two Bulldogs at 9.8 years are not big dogs at all. They're flat-faced.

The predictor nobody asks about

In the same data, muzzle shape outperformed size:

Muzzle	Example breeds	Median lifespan
Medium (mesocephalic)	Labrador, Beagle	12.8 years
Long (dolichocephalic)	Greyhound, Collie	12.1 years
Flat (brachycephalic)	Bulldog, Pug, French Bulldog	11.2 years

The gap from medium-muzzled to flat-faced is 1.6 years — double the whole size effect. And it compounds with size: medium-sized flat-faced breeds died 2.69 times faster than small long-muzzled ones, 9.4 years against 13.3.

Note the middle row before you draw the obvious conclusion, because the obvious conclusion is wrong and we nearly published it that way: long muzzles are not best. Long-muzzled breeds sit behind medium-muzzled ones. The famous "small long-nosed dogs live longest" claim comes from the small-and-long-muzzled combination reaching 13.3 — an interaction, not a main effect.

What else the study found

Female dogs outlived males, 12.7 to 12.4 — a small but consistent gap.
Purebreds outlived crossbreeds, 12.7 to 12.0. That runs against the usual hybrid-vigour story. Treat it carefully: crossbreeds are heterogeneous by definition, and the paper can't assign them size or muzzle categories at all.
Some medians rest on very few dogs. The Caucasian Shepherd's 5.4 years comes from 52 dogs, and thirteen breeds have no upper confidence bound because the sample was too thin to compute one. The table shows you which.

How to use this

Find your breed in the table, not your size bucket. That's the whole point of this page.
Read the confidence interval next to it. A median of 14.2 with an interval of 14.1–14.3 (Border Terrier, 9,387 dogs) is a much firmer number than 14.9 with no upper bound at all (Bolognese, 182 dogs).
Remember it's a median, not a verdict. Half of every breed lived longer. And these are populations — your individual dog is not a distribution.
Work out where your dog is in its own life, which is the more useful question. Our dog age calculator uses these same breed medians to place your dog in the AAHA life stages.
Keep them lean. Of everything on this page, it's the one lever you actually control — and unlike breed and muzzle, you can still change it today.

A note on the numbers you'll see elsewhere

You'll find lifespan-by-size figures attributed to the AVMA — 8–11 years for small dogs, down to 6–7 for giant breeds. Those are considerably more pessimistic than what this study measures (12.7 for small dogs). The AVMA page attributes its figures to an American Kennel Club expert-advice article, but publishes no methodology, sample size or study. When an unsourced figure and a 584,734-dog peer-reviewed study disagree by four years, we go with the study — and tell you we did. More on that in our guide to dog age, where the sourcing gets stranger still.