Medium breed

How long do Mixed Breed (Medium)s live?

A Mixed Breed (Medium) typically lives 11.4–14 years, from the age-conditioned veterinary life tables behind the Tailmates longevity score. Always a range, never a date.

Medium · ~20 kg adult

12.7

median years

11.4–14

typical range

~10

senior around

Median and typical range computed from the breed’s life table. Senior is the AAHA guideline that a dog enters its senior years in the last quarter of its typical lifespan, a size-band guide your vet tailors to your dog.

The curve, not a countdown

Already 2+ years old? The outlook is better than subtraction.

These numbers are conditional on the age your dog has already reached. A dog who’s made it to midlife has cleared the early risks that pull the breed average down. So the honest answer is more than “lifespan minus age.”

A Mixed Breed (Medium) aged…	Typically has ahead
2 years	10.1–13.1 more years (center ~11.6)
5 years	8.1–11.8 more years (center ~10)
8 years	6.3–10.6 more years (center ~8.5)
10 years	5.1–9.9 more years (center ~7.5)
12 years	4.1–9.3 more years (center ~6.7)

Gompertz-Makeham conditional survival curve for medium breeds (Montoya et al. 2023, n≈13.3M). Population statistics, not a prediction for any individual dog.

Walking needs

How much should you walk a Mixed Breed (Medium)?

Around 60–90 minutes a day — most medium breeds happily take more.

Band-level guidance, not a prescription. Age, health, and your vet’s advice come first.

Walks on the curve

What daily walks do to the longevity math

In the Tailmates model, a 28-day rolling window of active minutes feeds a saturating curve, the first minutes matter most, and it moves the estimate up by at most +0.5 years, never down. Bounded on purpose: activity has no published year-delta, sick dogs simply move less, and a walk you forgot to log looks exactly like a walk you never took. For a steady daily habit:

+0.2 yr

20 min/day

activity signal

+0.3 yr

40 min/day

activity signal

+0.3 yr

60 min/day

activity signal

The bigger walking payoff is indirect: lean body condition, the strongest modifiable lever in the model. For a medium breed like the Mixed Breed (Medium), ideal body condition reads +0.5 yr (capped at the +1.8-year effect from the Kealy lean-feeding trial), while carrying extra weight reads -0.8 yr and obesity -1.5 yr. Daily walks are how most dogs stay on the right side of that line.