How to predict a puppy's adult weight
A simple, widely used estimate is: adult weight ≈ (current weight ÷ age in weeks) × 52. It works best between about 8 and 16 weeks, when growth is steady. Because small breeds finish growing sooner and large breeds later, we nudge the estimate up or down slightly for breed size.
What affects the result
Genetics is the biggest factor — if you know the parents' sizes, the adult dog usually lands between them. Nutrition and neutering timing can also shift final size. Treat this as a ballpark, not a guarantee.
Frequently asked questions
My puppy is under 8 weeks — is this accurate?
Very young puppies grow unevenly, so estimates are rough. Recheck at 12–16 weeks for a better figure.
Why adjust for breed size?
Large breeds keep growing for up to 18–24 months, so a straight formula underestimates them; small breeds finish earlier, so it can overestimate.