Puppies grow quickly, but not all at the same pace. Smaller breeds tend to reach their full size sooner, while larger dogs take longer as their bones and joints need additional time to develop. Understanding your puppy’s growth timeline helps you plan for their care, from nutrition and exercise to choosing appropriately sized supplies.
In This Article
Puppy Growth Chart By Percentage
All numbers are approximate. Consult your veterinarian if in doubt.
|
Small (0-20 lbs) |
Medium (21-50 lbs) |
Large (51-100 lbs) |
X-Large (100+ lbs) |
|
|
6 months |
75% fully grown |
66% |
60% |
50% |
|
9 months |
90% |
85% |
75% |
65% |
|
12 months |
100% |
95% |
85% |
80% |
|
15 months |
100% |
100% |
95% |
90% |
|
18 months |
100% |
100% |
100% |
100% |
How Long Do Puppies Grow?
Puppies are considered adult dogs at around 1 year old, but their bodies may continue to grow and develop beyond that point. Most puppies grow in height and size while their bones are still forming, which can take anywhere from 6 to 24 months.
“The long bones in a puppy’s legs grow from two distinct places called growth plates,” according to Dr. Jerry Klein, DVM and Chief Veterinarian for the AKC. “The growth plates are somewhat flexible and soft during puppyhood when new tissue is being formed.”
As your puppy matures, these growth plates gradually harden. “When the growth plates have stopped producing new tissue and become completely calcified, they are said to have ‘closed,’ which means that they’ve stopped growing and the bone has reached its final size,” says Dr. Klein.
Even after skeletal growth is complete, puppies will continue to develop muscle and body fat as they transition into adulthood.
When Do Smaller Puppy Breeds Finish Growing?
Small and medium puppy breeds grow up pretty quickly. In fact, those petite puppies finish growing at around half the age of their larger counterparts, according to Dr. Klein. “On average, small breeds typically stop growing by the time they reach 6 to 8 months of age.”
Medium breed puppies might take just a bit longer to grow, reaching their adult size at around 12 months of age.
When Do Larger Puppy Breeds Finish Growing?
A larger dog takes a bit more time than a smaller one to reach full adult size because those bigger bones need more time to grow. “Giant breed puppies grow until they are 12 to 18 months old,” says Dr. Klein.
Large to giant breed puppies usually weigh 70 or more pounds as adults. In some cases, very large breeds like Mastiffs may not even reach their fully grown size until 24 months of age.
When Do Purebred Puppies Finish Growing?
If you’ve recently acquired a purebred AKC-registered puppy, then the breeder can let you know approximately how large your puppy will get and the expected growth rate based on their experience with other members of the puppy’s family tree.
“Purebred dogs are known first and foremost for their predictability: predictability of size, coat, temperament, etc.,” says Dr. Klein. “Granted, there will be variances within members of each breed (and each litter), but generally speaking, the breed can certainly help determine final size at adulthood.”
When Do Mixed-Breed Dogs Finish Growing?
For mixed-breed puppies, determining their growth rate can be a little more tricky. “When dealing with a dog of unknown heritage, it becomes a bit of a guessing game as to determining the final size,” says Dr. Klein. This is especially true for younger puppies between 6 and 10 weeks of age.
“A helpful hint is that if you run your hands down a dog’s rib cage and you can still feel the ‘knobs’ of the ribs, that dog will probably continue to grow in height,” recommends Dr. Klein. That’s because these “knobs” are the growth plates of the ribs that are still developing.
How Do I Feed a Growing Puppy?
Proper nutrition plays a critical role in healthy development. Puppies should be fed foods that meet the nutritional standards established for growth and development.
“Those foods designated for ‘all life stages’ mean that they meet needs of both growing and adult animals,” according to Dr. Klein. These diets can support your dog throughout their life, while puppy-specific formulas are typically fed until around 11 to 14 months of age.
It’s important to follow feeding guidelines carefully to avoid overfeeding. “It is known that obesity in puppies can lead to a predisposition of future orthopedic issues later in life, such as hip dysplasia, so a fit, leaner puppy is considered preferable to a chubby older puppy,” warns Dr. Klein.
What Should Large Breed Puppies Eat?
Large and giant breed puppies have specific nutritional needs that differ from smaller dogs. Their growth must be carefully managed to support proper bone development.
Too much calcium can be harmful during this stage. “This is because large and giant breeds are more sensitive than smaller ones to an excess or shortage of calcium while their bones are growing,” says Dr. Klein.
When choosing food, owners should look for formulas specifically designed to support the growth of large-breed puppies and ensure balanced nutrient levels.
How Much Exercise Do Growing Puppies Need?
Exercise is important for a puppy’s development, but too much activity can put stress on growing bones and joints. Puppies benefit from regular, moderate exercise rather than intense or prolonged activity.
“It is imperative to know that excessive, prolonged activity, like jogging, can be extremely detrimental on the bones and joints of growing puppies,” warns Dr. Klein.
“This is why it is never recommended to do road work or jogging on a dog less than 14 to 18 months of age, especially large and giant breeds, until the growth plates have fully fused,” says Dr. Klein.
Short walks on softer surfaces, such as grass, are generally safer while your puppy is still developing.
Key Takeaways
- Puppies may continue growing anywhere from 6 to 24 months depending on size
- Small breeds mature faster, while large and giant breeds take longer
- Growth plates determine height and close when development is complete
- Proper nutrition and controlled exercise are essential during growth
- Mixed-breed size and timeline can be less predictable
Frequently Asked Questions
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When do puppies stop growing completely?
+
Most puppies stop growing in height by 12 months, but large and giant breeds may continue developing until 18 to 24 months.
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How can I tell if my puppy is still growing?
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If your puppy is still gaining height or you can feel developing growth areas along the ribs, they are likely still growing.
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Do puppies keep gaining weight after they stop growing taller?
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Yes, after skeletal growth ends, puppies continue building muscle and body fat as they mature into adult dogs.
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Does neutering or spaying affect growth?
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It can influence growth timing slightly, but overall size is primarily determined by breed, genetics, and nutrition.
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