When Do Dogs Stop Growing?

Puppies grow at different rates depending on the breed but still, most owners want to know  … when do dogs stop growing? Whether you’ve got a miniature or giant breed puppy, each has its own growth rate to help you anticipate what size your dog will be at maturity. 

When Do Small Dogs Stop Growing?

Small breeds are those under 25 pounds at maturity. They have a shorter growth window, anywhere between 6 and 8 months. 

Popular toy breeds and small breed dogs include:

• Toy Poodle
• Chinese Crested
• Havanese
• Chihuahua
• Dachshunds
• Pug
• Pomeranian
• Maltese
• Yorkshire Terrier
• Papillon
• Shih tzu

Medium breeds are 25 to 50 pounds, and usually reach maturity by 12 months.  

Common medium breeds include:

• Australian Shepherd
• American Foxhounds
• Beagle
• Basset Hound
• Cocker Spaniel
• Border Collie
• Bearded Collie
• Brittany Spaniel
• Bull Terrier
• Portuguese Water Dog

When Do Large Dogs Stop Growing?

A dog that weighs 50 to 100 pounds when fully grown is a large breed and will reach maturity by 10 to 18 months of age. This is just an estimate as other factors can influence growth rates.

Some giant breeds like Mastiffs and St Bernards can continue to grow for 24 months. But most large dog breeds will stop growing in height by 16 months. They will continue to fill out and gain weight for another 6 months.

Large breed dogs include:

• German Shepherd
• Labrador Retriever
• Samoyed
• Siberian Husky
• Alaskan Malamute
• Akita
• Collie
• Dalmatian
• Bernese Mountain Dog
• Boxer
• Greyhound

Giant breed dogs include:

• Leonberger
• Great Danes
• Irish Wolfhound
• Newfoundland
• Great Pyrenees

Giant breeds take longer to mature, both mentally and physically. Their joints can become injured easily so it’s important to be very cautious with exercise for their first 18 months and up to 2 years.

Here are some factors that affect growth ... 

Can You Make Your Dog Grow Bigger?

It’s not that you want your puppy to grow bigger, but you want him to reach his potential size in a healthy way  … and that begins with a nutritious diet. You don’t want to over-feed as that can cause him to grow too fast. It can stress developing bones and joints and lead to joint issues and orthopedic problems like OCD (osteochondritis dissecans) or panosteitis.  

The best diet for your puppy is a fresh, whole food diet. Puppies need a diet balanced with the right amount of calcium and phosphorus, important minerals in bone and meat. Diets high in carbohydrates can be a problem as they provide excess starchy foods that lead to weight gain … and that can lead to joint issues too.

If you’re feeding your puppy a dry diet, look for foods that contain at least 26% protein. There are foods designed for all life stages and several that provide nutritional needs specifically for  puppies. 

But ideally, you want to feed your puppy a whole food, raw meat diet. It should include at least 14% protein and no more than 10% fat, as fed. There are several good quality commercial options that are balanced for your puppy’s needs. 

Your puppy also needs short amounts of exercise plus lots of rest. You want to avoid long periods of high intensity exercise as this can damage his growing joints. More strenuous activities like dock diving, agility training and long runs with you are activities he can do when he matures, but not before. Frequent walks will keep your puppy happy and prevent him from becoming overweight.

RELATED: How to feed a raw diet ...

Does A Dog Grow After 6 Months?

Most of your puppy’s growth will take place in his first 6 months of life. But he’ll continue to grow in weight and height until he is full grown and that could take a few more months. 

A toy breed or small dog breed is usually fully grown in that first 6 months. Medium breed puppies and large breed puppies will reach about two-thirds of their adult weight by 6 months. But giant breed puppies will only be about half of their adult size by 6 months. 

How Big Will My Puppy Get?

There are several ways to determine how big your puppy will get at maturity. The best way to estimate your puppy’s adult size is by his breed. It’s thought that the size of your puppy’s paws is a good predictor ... but that’s just a myth. 

There are dog breed standards for purebred dogs that are fairly accurate. And there are puppy weight calculators based on these standards that will help predict how big your puppy will get. 

When Do Mixed Breed Puppies Stop Growing?

If you’re wondering when your mixed breed puppy will stop growing, it’s a little harder to predict. And his size can be a guessing game too. When you know the breeds involved and the size of the parents you can get a better idea. Otherwise you can use the possible breed or breeds to estimate his adult size. 

After using one of these calculators, the results might show that your mixed breed puppy is underweight or overweight … and yet he seems to be a healthy weight. This might indicate your puppy’s parents were larger or smaller than you thought. That makes it harder to determine when your mixed breed dog will stop growing.

Do Puppy Weight Calculators Work? 

These calculations will estimate the adult size of your dog but it isn’t a perfect science.

There are many variables that affect your dog’s growth and size  including:

• Genetics
• Pedigree
• Gender
• Spay/neuter history and age

Of course, these puppy weight calculators have better accuracy if you have a purebred puppy. But your dog may grow bigger or smaller than the estimate … and that’s okay … you just want to make sure he’s healthy and happy.

RELATED:  The risks of early neutering ... 

My Puppy Isn’t Growing Or Gaining Weight

Puppies are usually eating machines so it’s not normal if your puppy isn't growing or gaining. It could be intestinal parasites like roundworms, hookworms or tapeworms which are common in puppies in North America. Your puppy can get them from his mother or from the environment. You’ll see physical signs in your puppy and slow growth but you’ll also be able to see tapeworm or roundworm in your puppy’s poop. Some worms are microscopic so you can’t see them in poop. 

If you suspect your puppy has worms or a parasite, you can take a poop sample to your vet for testing. If you’ve got a conventional vet, he will probably recommend harsh pharmaceutical dewormers. Instead, there are many natural and food-based remedies that fight worms quite successfully. Giving your puppy a fresh, whole food diet is the first step to preventing worms naturally.

RELATED: Natural ways to get rid of worms in dogs ...

Last Word

So when do dogs stop growing?… Once again, there isn’t a clear cut answer. The best estimator of your puppy’s full size is based on his breed. And a puppy weight calculator may help narrow it down if you’ve got a purebred puppy. But ultimately, any puppy will build good health and grow to his full potential if he’s fed a well balanced, whole food, raw meat diet.