How much will my puppy weigh as an adult?
Enter your puppy's current weight, age in weeks, and expected adult size to estimate their adult weight.
Estimated adult weight
13.0 kg
Likely range: 11.1 to 15.0 kg.
How the calculation works
The estimate starts from a simple proportion rule: adult weight ≈ (current weight ÷ age in weeks) × 52 weeks, assuming a steady growth rate throughout the first year.
Since different sizes grow for different lengths of time — small dogs mature faster, giant breeds keep growing for longer — we apply an adjustment factor to the base result based on the expected adult size.
The result is always shown as a range (not a single number), because factors like genetics, nutrition, and health during growth cause natural variation around the estimate.
Frequently asked questions
Is this estimate reliable for any breed?
It's a general estimate based on growth patterns by size, not by specific breed. Breeds with atypical growth curves (such as very brachycephalic breeds or slow-growing giant breeds) may deviate more from the estimate.
Up to what age does this calculation work well?
The formula is most reliable between 8 and 52 weeks (up to 1 year of age). After that, the dog should already be close to their adult weight and the extrapolation loses accuracy — which is why we show a warning in those cases.
Why does the expected adult size affect the result?
Small dogs reach their adult weight faster (usually between 8 and 12 months), while large/giant dogs keep growing until 18-24 months. That's why we apply a different adjustment factor for each size.
My puppy is a mixed breed. How do I choose the size?
Look at the puppy's paw size and bone structure, or consider the average size of the parents, if known. If unsure, choose "medium" as a neutral estimate.
Important notice
This calculator is for educational purposes and does not replace a veterinary evaluation. When in doubt, consult a veterinarian.Sources
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