Growth · July 13, 2026 · 6 min read
Bernese Mountain Dog Growth Chart: What to Expect
Bernese Mountain Dogs are large-breed dogs that grow rapidly but don't reach full maturity until 18–24 months. Here's what healthy growth looks like at each stage.
Watching a Bernese Mountain Dog puppy grow is remarkable — these dogs go from small, fluffy bundles to large, imposing adults in under two years. But that rapid growth, combined with the breed's known vulnerability to developmental orthopedic disease, makes it important to understand what healthy growth looks like and how to support it without pushing it faster than the skeleton can safely handle.
Bernese Mountain Dogs are classified as a large breed. Large breeds mature more slowly than small and medium breeds, with growth plates closing around 12–18 months and full physical maturity — in terms of muscle mass and body weight — typically reached between 18 and 24 months. Adult weight range is 32–52 kg (71–115 lb); adult height ranges from 58–70 cm at the withers.
Birth to 3 months: rapid early growth
Bernese Mountain Dog puppies are born weighing roughly 400–600 g and grow quickly in the first weeks of life. By 8 weeks — the typical rehoming age — a healthy Berner puppy generally weighs between 6 and 10 kg. Their dense tricolor coat begins developing early, and they may look chunkier than they actually are even at this age.
From weaning to about 8 weeks, nutrition comes primarily from the dam. After rehoming, large-breed puppy food softened with water (initially) and then fed dry provides the appropriate nutritional base. Three meals per day through the early puppy phase helps maintain stable blood sugar and limits the stomach load at any one sitting.
3 to 9 months: peak growth phase
This is the period of most rapid weight gain and height increase. Berner puppies may gain 3–5 kg per month during this phase. By 6 months, many are already 25–35 kg — looking almost like adult dogs in overall size but still carrying puppy proportions and immature joints. Males tend to be heavier than females throughout the growth period.
Large-breed puppy food is essential during this phase. The controlled calcium and phosphorus levels and moderate energy density in large-breed formulas support measured skeletal growth and reduce the risk of osteochondrosis dissecans (OCD), hypertrophic osteodystrophy (HOD), and other developmental orthopedic conditions. Do not supplement with additional calcium — a complete large-breed puppy food already provides appropriate amounts, and excess calcium in a large-breed puppy can cause bone abnormalities.
9 months to 2 years: filling out and maturing
Height at the withers largely stabilizes for most Berners by 12–15 months (within the adult range of 58–70 cm), but the dog continues to broaden, deepen in the chest, and add significant muscle mass through 18–24 months. Body weight continues to increase during this period even after height is essentially complete.
Many owners transition to adult food too early, often around 9–12 months when the puppy looks close to adult height. For Bernese Mountain Dogs, the recommendation is to continue large-breed growth or all-life-stages food until 18–24 months. Switching too early may sacrifice the joint-protective nutrient balance the puppy still needs.
Common growth misconceptions in large breeds
A common myth is that you should restrict food intake in a large-breed puppy to prevent joint problems. Controlled growth through appropriate large-breed puppy nutrition is the correct approach — not calorie restriction or a food designed for adult maintenance, which may not meet growing needs. Underfeeding a puppy causes nutritional deficiencies and stunting; overfeeding above appropriate large-breed puppy amounts increases joint risk. The goal is to feed to an appropriate, lean puppy body condition (BCS 4–5).
Another misconception is that raw-fed or grain-free diets protect large-breed puppies from joint problems. There is no peer-reviewed evidence supporting this. Some boutique or grain-free diets may not meet the specific calcium-phosphorus ratios established for safe large-breed puppy growth. AAFCO-compliant large-breed puppy formulas remain the most reliably safe nutritional baseline for growing Berners.
Monitoring growth and involving your vet
Routine puppy vet visits at 8, 12, and 16 weeks, then 6 months and 12 months, give your vet the opportunity to track growth trajectory and assess joint development. Bernese Mountain Dogs are predisposed to hip and elbow dysplasia, and early signs — lameness, reluctance to exercise, swollen joints, bunny-hopping gait — should be evaluated rather than attributed to "growing pains."
Hip and elbow evaluations (PennHIP or OFA screening) can be done once the dog is skeletally mature; many Berner owners elect formal screening at around 24 months. If you have concerns about your puppy's growth rate or gait before that age, an earlier veterinary assessment is worthwhile.
Frequently Asked Questions
How fast do Bernese Mountain Dog puppies grow?
Very quickly — gaining 3–5 kg per month during the peak growth phase (3–9 months). Most height is established by 12–15 months, but they continue filling out in muscle and body mass until 18–24 months.
When is a Bernese Mountain Dog fully grown?
Berners reach their adult height of 58–70 cm by around 12–15 months, but don't reach full adult weight (32–52 kg) and muscular maturity until 18–24 months.
Do Bernese Mountain Dogs need large-breed puppy food?
Yes. Large-breed puppy formulas provide controlled calcium, phosphorus, and energy levels that support healthy skeletal development in large breeds. They should be fed until 18–24 months of age.
Medical Disclaimer
This tool provides general, educational estimates and is not a substitute for professional veterinary advice, diagnosis, or treatment. This article provides general educational information and is not a substitute for professional veterinary advice. Always consult your veterinarian about your pet's specific health needs before making changes to their diet, water intake, or care routine.
Put This Into Practice
Puppy Growth Calculator
Track your Berner puppy's growth and estimate adult weight.
Puppy Feeding Calculator
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Body Condition Score Calculator
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Bernese Mountain Dog Breed Profile
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