Puppy Weight Calculator
Predict a puppy's adult weight from its current weight and age.
About the Puppy Weight Calculator
A common rule of thumb for small and medium breeds is (current weight ÷ age in weeks) × 52. Large and giant breeds grow longer and more slowly, so their adult weight is often estimated as about twice the weight at 6 months. Both are rough: breed, sex, neutering and nutrition matter, and parents' weights are the best guide.
The formula
Adult ≈ weight ÷ age (weeks) × 52
Worked example
Example: Estimated adult weight = 45.1 lb
- Inputs: Weight in: lb; Puppy's current weight: 13; Age: 15 weeks; Expected size: Medium.
- Formula: Adult ≈ weight ÷ age (weeks) × 52
- Result: Estimated adult weight = 45.1 lb
Things to keep in mind
- An estimate only; mixed breeds vary widely.
Questions people ask
Do paws predict size?
Loosely; big paws often mean a big dog, but not reliably.
When should I switch to adult food?
Around 12 months for most, 18–24 months for giant breeds.