Puppy feeding and growth
How much should my puppy weigh at 3 months?
Last updated 23 September 2026 · How we write and check this
Short answer
At three months a puppy is typically somewhere between a quarter and half of its eventual adult weight, though this varies by breed. A small breed might already be close to half its adult weight, while a giant breed is often still well under a quarter of the way there.
Rough proportions by size category
As a general pattern, small breeds tend to reach around 40 to 50 percent of adult weight by three months, medium breeds around 30 to 40 percent, and large and giant breeds often only 20 to 30 percent, because their overall growth period stretches out much further.
Working backward from expected adult size
If you know or can estimate the puppy's likely adult weight, for example from the breed standard or from the size of its parents, you can sanity check whether the current weight is roughly in the expected proportion rather than comparing against an unrelated general figure.
When proportions look off
A puppy tracking well below the expected proportion for its breed over several consecutive weeks, especially alongside low energy or a dull coat, is worth discussing with a vet, since it could point to an underlying feeding gap or a health issue affecting growth.
Key takeaways
- At three months, small breeds are often near half their adult weight, giant breeds far less.
- Working from expected adult weight gives a more useful benchmark than a flat number.
- Growth proportion at this age varies mainly by size category, not just breed identity.
- Persistent low growth relative to breed expectations is worth a vet discussion.