At What Age Do Beagles Stop Growing?

If you have a beagle puppy, you are probably watching them grow and wondering when they will reach their full size. Beagles go through a rapid growth phase during their first year, but they do not finish filling out until a bit later. Here is what to expect at each stage and how to tell if your beagle is growing at a healthy rate.

When Do Beagles Stop Growing?

Most beagles reach their full height by 8 to 12 months of age. However, they continue to fill out and add muscle until they are about 18 months old. So while your beagle may stop getting taller around their first birthday, they will keep getting broader and more muscular for several more months after that.

The distinction between “full height” and “full size” matters. A 12 month old beagle might be as tall as they will ever get but still look lanky and adolescent. By 18 months, they will have the filled out, adult body shape that is characteristic of the breed.

Adult Beagle Size

There are two recognized beagle size varieties. The smaller variety stands under 13 inches at the shoulder and weighs 20 to 22 pounds. The larger variety stands 13 to 15 inches and weighs 22 to 30 pounds. Most pet beagles fall in the 13 to 15 inch range.

Males tend to be slightly larger and heavier than females, though the difference is less dramatic than in many other breeds. A typical male beagle weighs 22 to 30 pounds, while females usually weigh 20 to 25 pounds.

Beagle Growth Timeline

Birth to 2 Weeks

Beagle puppies are born weighing about 5 to 10 ounces. They are blind, deaf, and completely dependent on their mother during this stage. Growth is steady but slow compared to what comes next.

2 to 8 Weeks

This is when rapid growth begins. By 8 weeks, most beagle puppies weigh 5 to 7 pounds. Their eyes and ears are open, they are walking and playing, and their personalities are starting to emerge. This is the age when most puppies go to their new homes.

3 to 6 Months

Growth is fast during this period. A 3 month old beagle typically weighs 7 to 10 pounds, and by 6 months they usually weigh 12 to 17 pounds. They are gaining height rapidly and may look a bit gangly, with legs that seem too long for their body. This is also the teething phase, so expect a lot of chewing.

6 to 12 Months

Growth starts to slow down but does not stop. By 9 months, most beagles weigh 17 to 22 pounds and have reached about 90% of their adult height. By 12 months, they are close to their full height and weigh 18 to 26 pounds depending on whether they are the smaller or larger variety.

12 to 18 Months

The final growth phase is mostly about filling out. Your beagle’s chest will deepen, their muscles will develop, and they will reach their adult weight. By 18 months, most beagles are at their full adult size. Some larger males may continue adding a small amount of weight until age 2.

Factors That Affect Growth

Genetics is the biggest factor in how large your beagle will get. If the parents are on the larger or smaller end of the breed standard, the puppies will likely follow the same pattern. Looking at the parents gives you the best prediction of adult size.

Nutrition plays an important role during the growth phase. Feed a high quality puppy food appropriate for medium breeds. Overfeeding can cause a beagle to grow too fast, which puts stress on developing joints. Underfeeding can result in a smaller adult size and nutritional deficiencies. Beagles are food obsessed, so it is up to you to control their portions since they certainly will not self regulate.

Spaying or neutering before full maturity can slightly affect final size. Dogs altered before their growth plates close may grow slightly taller than they would have otherwise, because the hormones that signal growth plates to close are removed. The overall effect is usually minor in a smaller breed like the beagle.

Is My Beagle the Right Weight?

Beagles are one of the breeds most prone to obesity. Their love of food combined with their relatively compact size means extra weight piles on quickly. Use the rib test to check your beagle’s weight: you should be able to feel the ribs with light pressure but not see them. When viewed from above, there should be a visible waist behind the ribs.

An overweight beagle is at increased risk for diabetes, heart disease, joint problems, and a shorter lifespan. If your beagle seems overweight, reduce treat intake and make sure they are getting enough exercise to match their active nature. Your vet can help you develop a weight management plan if needed.

When to See a Vet About Growth

If your beagle puppy seems significantly smaller or larger than expected for their age, or if their growth seems to have stalled, check in with your veterinarian. Some conditions like intestinal parasites, thyroid issues, or nutritional deficiencies can affect growth. Your vet can evaluate whether your beagle is developing normally and recommend any necessary interventions.