Do big paws mean big dog?

When Do Dogs Stop Growing? Finding Your Pup’s Final Size!

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One of the most rewarding things about puppies is watching them grow.

But just like most other mammals, dogs eventually reach their mature size and stop getting bigger.

Small breeds stop growing at around 6 to 8 months of age. Medium-sized dogs stop growing at around 12 months, and large-breed dogs stop growing around 12 to 18 months.

Large-breed puppies take longer to reach their full size because their larger bones need more time to grow. However, there’s plenty of wiggle room involved, and some dogs stop growing much sooner or later than the 1-year mark.

We’ll talk about these differences and some of the things that influence your dog’s progress from puppyhood to adulthood below.

Key Takeaways: When Do Dogs Stop Growing?

• In most cases, dogs stop growing between 6 and 18 months of age.Generally speaking, small breeds stop growing at younger ages than large breeds do.
• Several factors can influence the length of time during which your pup will continue to grow.However, the two most important factors are likely your pup’s genes and the food you provide your pooch.
• Spaying and neutering may have a very small influence on the ultimate size of your pooch. However, these differences are essentially negligible and only become obvious when you review mountains of data.

How Do Puppies Grow, Anyway?

Anatomically speaking, dogs grow in much the same way that human children do – especially as it concerns height.

It’s easy to intuit the growth of your puppy’s muscles and other soft tissues; after all, muscles can grow throughout a dog’s life. Many mature dogs could even “bulk up” if put through an exercise regimen that included resistance training and proper nutrition.

But bones are different. They don’t grow at all during adulthood, and it is harder to envision the way by which they increase in size early in your pet’s life.

Rather than growing in a generalized manner that encompasses the entire bone, the long bones in a puppy’s legs grow from two distinct places called growth plates. Located at each end of the bones, growth plates are relatively thin cartilaginous regions in which new tissue is created.

The growth plates are somewhat flexible and soft during puppyhood when new tissue is being formed.

As the new tissue ages, it hardens and calcifies, eventually becoming bone. 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.

Growth plates are actually somewhat fragile and vulnerable to injury. So, it is important to prevent young puppies from engaging in excessive amounts of exercise, which may damage the growth plates. It’s also a bad idea to let pups jump great heights, such as onto or off of the couch.

Size and Breed-Related Puppy Growth Factors

It turns out that small dogs stop growing sooner than large dogs do.

This makes sense, as large breeds grow much more between the day they’re born and the day they stop growing than small breeds do.

Consider, for example, that Chihuahua puppies are born weighing about 5 ounces, and they reach about 5 pounds or so at maturity. This means they increase their size by a factor of 15.

On the other hand, a Great Dane puppy weighs about 1 pound at birth and 100 pounds or more at maturity.

This means that they exhibit a 100-fold difference in size over the course of their lives (and 200-pound Great Danes experience twice this much growth!).

Because it takes time to convert food into new tissue, large breeds must continue to grow over a longer period of time than their smaller counterparts.

On average, small breeds typically stop growing by the time they reach 6 to 8 months of age, but giant breeds grow until they are 12 to 18 months old.

Larger breeds can end up costing quite a bit more, as a perfectly sized puppy bed won’t last too long with a young Newfoundland.

This is also something to keep in mind with selecting a crate for your pup – you may be better off opting for a larger-sized crate and using dividers to keep the space suitably-sized until your growing dog needs more room!

Other Factors that Alter Puppy Growth Rate

Aside from your dog’s breed, there are a few other factors that can influence his growth rate and ultimate size. Two of the most important such factors include:

1. Genetic Differences

Every dog has a unique genetic code which can significantly influence the duration of his growth period, his build, and his adult size.

Some genetic traits are passed down from parent to puppy, but others are simply the result of the random variation that occurs during DNA recombination.

This means that puppies from large parents may themselves exhibit a slightly longer growth period and larger eventual size, but it is certainly not guaranteed. Large parents will occasionally produce small offspring and vice versa.

2. Nutrition

Puppies fed a poor diet may not be able to obtain all of the minerals and protein they require to grow into big, strapping canines.

Therefore, to maximize your pup’s potential (and generally keep him healthy), you’ll want to feed him a high-quality food specifically designed for puppies.

Such foods have higher protein content and are specifically formulated to provide puppies with the things their growing body’s need.

Note that if you have a large breed puppy, you’ll want to select a food designed specifically for them. Large puppies who grow too quickly can suffer from orthopedic problems later in life.

How Does Spaying or Neutering Affect Puppy Growth Rate?

There are a lot of myths and misunderstandings about the ramifications of neutering or spaying, and many owners believe that their dog will stop growing sooner or won’t grow as large if they alter their pet.

Technically, spaying and neutering are thought to trigger very subtle changes in the growth rate trajectory of puppies (pack a lunch before visiting that link) and they can influence the adult size of a dog very slightly.

However, this change in adult size occurs in the opposite direction than most owners suspect: Dogs altered before 16 weeks of age actually grow a bit bigger than those who aren’t spayed or natured at this age do.

Nevertheless, hormones aren’t the primary drivers of growth – genetics and nutrition are.

The differences brought about by neutering and spaying procedures only become apparent when you look at buckets full of data, representing thousands of individuals.

Your decision to spay or neuter your pet shouldn’t change his adult size in an appreciable way. Still, you’ll likely want to read up on the pros and cons of spaying and neutering your dog to get a better understanding of when to get your dog sterilized.

The Adult-Sized Puppy Phenomenon

Note that many large breeds remain within the mental and emotional bounds of puppyhood for long after they’ve stopped growing.

They may have reached their full size and passed their second birthday, but they still have that lovable puppy face. Many also maintain a goofy, playful puppy-like demeanor at this time.

It isn’t entirely clear why this occurs, but it may be related to social factors.

Puppies exhibit a lot of the same facial characteristics that other young animals do, including big eyes and rounded faces, among other things. These traits are thought to help encourage tolerance and care-taking behavior in adults.

So, their puppy-like features may help prevent adult dogs from taking exception to their social faux pas.

Puppy Growth FAQs

At what age is a dog fully grown?

Small breeds tend to stop growing at 6 to 8 months of age. Medium breed puppies tend to reach adult size at around 12 months. Large breed dogs generally stop growing at 12 to 18 months.

Can you tell how big a puppy will get?

You can guess how big a puppy will get based on the expected adult size is for that breed. Paws can also provide clues for how big a puppy will get. Large paws on a puppy are generally a sign that the pup will grow into a larger-sized dog. The best way to estimate how big your puppy will get is through a dog DNA test!

How much will a dog grow after 6 months?

Your dog’s growth trajectory after 6 months will largely depend on their breed and expected adult size. Small breed dogs will be close to their full size at 6 months, whereas larger dogs will be 2/3 of their adult weight. Giant breeds will be at around half of their full adult size.

Have you ever had a dog that grew for an exceptionally long or short period of time? I’ve always kept big dogs, so I’m used to watching them grow for about 12 to 18 months. My Rottie reached her final height at about 16 months of age, but she continued filling out for another year or so.

Let us know about your pooch’s growth in the comments below!

Growth in Dogs: What to Expect

If a young dog has joined your pack recently, you likely have questions about what the first year or so in her life will look like from a developmental perspective. When will she stop growing? What do those big paws really mean? Dr. Susan O’Bell, a primary care doctor at Angell Animal Medical Center in Boston, and Dr. Matthew Rooney, owner of Aspen Meadow Veterinary Specialists in Longmont, Colo. and a board-certified specialist in surgery, have the answers.

When Do Dogs Stop Growing and How Big Will My Puppy Get?

Most dogs’ growth plates close at around 9 to 11 months of age, the doctors say. By that point you should have a good sense of your dog’s ultimate height and length, with giant breeds growing until they are a little over a year old, O’Bell says. Smaller dogs reach full growth a bit sooner, between six and eight months, Rooney says.

“Many medium and large breed dogs retain a ‘juvenile’ appearance for their first one to two years of life, but technically they aren’t still growing,” O’Bell says. So, although your dog’s demeanor and behavior can still appear juvenile, and sometimes their features retain that “puppy” look (with a coat of soft hair, rounded facial features and ears and a narrower chest), your dog should no longer be growing after it turns two.

If you know the breed of your dog or, better yet, the parents of your pup, you can estimate how large your dog will be from that, Rooney says. Otherwise, it can be tough. One of the best predictors of ultimate stature are your dog’s siblings, O’Bell says. If you can check out a previous litter of the same sire and dam, you will get a glimpse of your dog’s future size. “For purebreds, there are some general ranges available, so your dog’s ultimate size shouldn’t be a huge surprise,” she adds.

Unfortunately, while pet parents are quick to comment on the size of a puppy’s paws and ears, they don’t tell us much about how big a dog will be. “We often comment about how big a puppy’s paws or ears are, but these are not reliable indicators,” O’Bell says. Rooney agrees that, while a puppy can have ears or paws that seem too large or small for their frame at the time, they don’t indicate how big that puppy will become.

What are Some Common Conditions to be Aware of in Growing Dogs?

“The most common concerns are orthopedic. Problems in the elbows, shoulders, hips and other joints mainly occur in larger dogs (50 pounds or more). Very small dogs can have hip or knee issues,” Rooney says, noting that most growing dogs will not be affected by these conditions.

Painful but short-lived bone inflammation, known as panosteitis, can affect young dogs and usually requires medication, O’Bell says. Large and giant breeds sometimes suffer from hypertrophic osteodystrophy, painful swelling of growth plates of the legs that is often accompanied by a fever. The condition usually resolves on its own, she says.

Some inherited and congenital conditions include hip dysplasia (when the ball and socket of the hip joint are not aligned correctly) and osteochondrosis (abnormal development of cartilage in the joints). Surgery is sometimes needed to correct these conditions, O’Bell says. Large breeds such as German Shepherds, Labradors and St. Bernards are among those prone to these conditions, according to the American Animal Hospital Association. If you see your dog limping or notice that one leg appears to be slightly twisted or angled, contact your veterinarian or a surgical specialist.

Do Dogs Experience Growing Pains?

Puppies don’t seem to experience growing pains, O’Bell says. However, some orthopedic conditions like those described above can cause symptoms in young dogs, including: limping, an abnormal gait or stance, or reluctance to participate in normal activities. Sometimes there will be heat, swelling and/or pain around the affected areas. Some inflammatory conditions are accompanied by a fever, which can make your dog lethargic and dull her appetite, she adds.

She also notes that most puppies are more high energy than adult dogs and may be more prone to minor injuries from rough play that can cause temporary discomfort.

Are Care Requirements Different for a Growing Dog?

All puppies should have periodic visits to their veterinarian, often three or four visits during their first year of life, O’Bell says. During these visits, your vet will assess your puppy’s growth, including weight gain and body condition. Use common sense when monitoring your young dog’s health by paying attention to her normal habits, raising any concerns you have with your vet and watching for signs of anything that seems off, Rooney says.

From a diet perspective, Rooney says to look for higher-protein dog foods to fuel your puppy’s growth. Large-breed puppies will also benefit from eating a large-breed puppy food because these products help prevent the too-rapid growth that increases their risk of developing orthopedic disorders. Your veterinarian can help you tailor your puppy’s diet to make sure she is gaining enough weight and receiving the proper amounts of nutrients, the doctors say. In addition to adequate protein, young dogs need higher amounts of fat than adult dogs and a proper balance of vitamins and minerals to support their growth and development. “Your veterinarian is an excellent resource if you have questions about selecting the most appropriate diet,” O’Bell says.

When it comes to exercise, puppies should have at least an hour of moderate activity a day, but anyone who has raised one or more puppies knows the right amount of exercise can vary, O’Bell says. Depending on the breed and age of your dog, she may be interested in or able to play for only a few minutes before needing a nap. Other puppies require longer periods of stimulation.

Strenuous exercise may pose only a theoretical risk to young dogs, O’Bell says, but she advises caution especially in large-breed dogs and those who may be predisposed to a condition such as hip dysplasia. “We wouldn’t want to damage their growth plates, especially when they are still growing,” she notes.

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