How much should a beagle puppy weigh at 3 months?

There's a wide normal range, but many beagle puppies are somewhere around a third to just under half of their eventual adult weight by three months. Your vet can tell you whether your individual puppy is tracking well at their check-ups.

When does a beagle stop growing?

Most beagles reach close to full adult size by around 12 months, with some minor filling out continuing to around 15 to 18 months. This is considerably faster than a large breed, which can take up to two years.

Is my beagle puppy underweight or overweight?

A chart gives a rough guide, but your vet can properly assess body condition at a check-up by feel as well as weight, which is more reliable than a number alone. Raise any concern about their growth at a routine visit.

Beagle puppy growth chart: what to expect

A beagle is a small-to-medium breed, with adults typically settling between 9 and 11kg, and most of that growth happens in the first six to eight months before slowing considerably. Reading a growth chart is about spotting a rough pattern, not chasing an exact figure for a specific week.

What a typical pattern looks like

A beagle puppy gains weight fastest in the first few months, often reaching around half its adult weight by four to five months old, then growth slows and most beagles are close to full adult size by around 12 months, with some minor filling out continuing until 15 to 18 months. Because beagles are a small-to-medium breed, this growth window is considerably shorter than a large breed's.

Individual beagles vary within that pattern based on litter size, parentage and general health, so a chart is a rough guide for spotting whether your puppy is broadly on track, not a target to hit exactly week by week.

How to use a growth chart sensibly

Weigh your puppy at consistent intervals — weekly in the first couple of months, then less often — using the same scale where possible, and look at the overall trend rather than reacting to any single reading. A puppy tracking steadily, even if it's above or below an average line, is generally more reassuring than one whose weight jumps around unpredictably.

If your beagle puppy seems to be growing much faster or slower than expected, or their body condition looks noticeably over or underweight to the eye, that's worth raising at a routine vet check rather than trying to interpret a chart alone.

Common questions

How much should a beagle puppy weigh at 3 months?: There's a wide normal range, but many beagle puppies are somewhere around a third to just under half of their eventual adult weight by three months. Your vet can tell you whether your individual puppy is tracking well at their check-ups.
When does a beagle stop growing?: Most beagles reach close to full adult size by around 12 months, with some minor filling out continuing to around 15 to 18 months. This is considerably faster than a large breed, which can take up to two years.
Is my beagle puppy underweight or overweight?: A chart gives a rough guide, but your vet can properly assess body condition at a check-up by feel as well as weight, which is more reliable than a number alone. Raise any concern about their growth at a routine visit.

Sources

Written against guidance published by UK veterinary and welfare organisations. Always confirm specifics with your own vet.

PDSA — Pet Health Hub

Written by Matt Garnett, who runs Giddy Pets and is a lifelong pet owner — not a vet. This is general information, not veterinary advice, and it cannot replace an examination by the vet who knows your animal. How we write these guides.