When do puppies stop growing?

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Across the canine world, no one pooch is the same, even within a breed. Shape, size, appearance and personality differ from one dog to the next, meaning every puppy is completely unique. This means that it’s almost impossible to foresee exactly when a puppy will stop growing, but there are a few ways to get a pretty good guess at it.

Maturing is a process that happens gradually over time. However, it might seem that one day you had a tiny pup that could fit in one hand and in the blink of an eye you’ve got a fully grown dog that can’t even fit on your lap.

The time it takes for a dog to stop growing varies massively, but breed size is one of the main factors that you can base it off. Most dogs will typically reach full size between 6-24 months of age, but this is a long time span and doesn’t really narrow it down that much.

We’re going to give you a few ways to help estimate how long it’ll take for your pup to become a fully grown pooch.

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Small to medium dogs

The rule generally goes, the smaller the breed, the quicker they’ll stop growing. The tiniest dogs, especially the toy breeds, will grow extremely fast and typically stop growing between 6 and 8 months of age - they’re the quickest to reach full size.

A dog of medium size tends to finish growing at around 12 months old.

Large to giant dogs

Large and giant breeds will appear to grow at a rapid rate when you first bring them home. However, this will slow right down, and they’ll continue growing at a more gradual pace up until around 12-18 months, possibly even 24 months! An exact answer is not paw-sible here as it can differ so much.

Bigger breeds may look like adult dogs a lot quicker because of their large size, but they actually remain puppies for a lot longer than smaller breeds. Reaching full size takes longer for bigger dogs as they have much bigger bones that require more time to grow.

Some speculate that the size of your pup’s paws can tell you a lot. If their paws look way too big for their body, it might be a sign that you’re going to have a humongous hound on your hands.

You might be starting to worry, questioning if your dog will ever stop growing. Before getting a puppy, make sure you know the standard size of your chosen breed, so you aren’t met with a shock when you find yourself with a beast of a dog when you actually wanted a tiny lapdog.

Crossbreed dogs

If you rehome a puppy, you may be unsure of their breed and heritage. This makes it basically impossible to determine their full size, you’ll just have to wait and see what you end up with!

Hybrid dogs are constantly growing in pup-ularity, such as Cockapoos, Labradoodles and Pomskys. Again, with a crossbreed pooch there is no exact, standardised breed size so it’s pretty tricky to know exactly how big they’ll end up.

However, you can take a rough estimate if you know the general sizes of the two breeds your puppy came from.

What else can influence growth?

As we know, no one dog is the same, and this is even true within one litter of pups! Every dog in a litter will differ slightly in size, especially between genders. Male dogs normally grow bigger than females.

The speed in which your puppy grows can be influenced by several other factors too:


Knowing all about your chosen breed and their genetic history will be enough to give you a rough guideline regarding their growth. This will make sure you’re not in for a shock when your pooch reaches their full size.

For instance, pups that are born from two larger parents are likely going to have a much longer growth period and reach a bigger final size.

However, this is not a definite, as some genes are passed down from parent to pup whereas some genes are simply random.

Diet and exercise

A healthy, balanced diet is fundamental to your pup’s development and growth into adulthood. Feeding your pooch a poor diet can cause their growth to stagnate as they’re not getting the appropriate amount of nutrients they require to grow into strong, healthy dogs.

Natural, wholesome puppy food packed full of high-quality ingredients is essential for a puppy to get the best from their diet. Pure curates a tailored menu of recipes for your pup that is nutrient-dense and caters to all their needs throughout their life stages from puppy to adulthood.

Alongside their dietary requirements, a dog parent should consider how much exercise is necessary for their pup. Exercise is essential for a puppy to build muscle and stamina, however too much exercise can be a problem. Overexercising a young pup can cause trauma and hinder joint growth.

Joints that haven’t had the opportunity to grow fully can cause problems for your pup’s growth, resulting in conditions such as arthritis and hip dysplasia.


Spaying or neutering your dog too early can inhibit development of their growth plates which can in turn cause joint issues. Supposedly, this can cause your dog to grow taller than they should.

Puppy growth timeline

Of course, every single breed is different. However, every puppy will encounter a similar developmental timeline.

Newborn-2 weeks

Honestly, not a lot happens here in the first two weeks. Newborn puppies won’t have gained their senses yet, snoozing all day and waking up for some food every so often. Sounds like an easy life!

2-4 weeks

From two weeks old, your pup will start to develop their senses. Their eyes will open and they’ll start learning how to walk. Around four weeks old is also where those dreaded, sharklike puppy teeth come through.

4-12 weeks

A lot happens between these weeks. Lots of playtime with their siblings, learning how to behave and starting to develop emotional responses to what they like and fear. Also, at 8 weeks old you can bring your new puppy home! The next few weeks are a pivotal time where strong bonds begin to form.

12-24 weeks

You will begin to notice your pup acquiring their own personality in these weeks, along with a lot of curiosity and mischief! Socialisation is key here so your puppy learns how they should act around both people and pooches. This is also the main teething stage, so prepare yourself for those sharp gnashers.

6-12 months

Here your dog becomes a teenager, and this is a notoriously difficult time in puppy ownership. Boundaries will be tested, they’ll outright refuse to listen and will become easily bored. Sounds a lot like a human teenager…

1-2 years

Most dogs should be fully grown at this stage and will have left the puppy mental state behind. However, many dogs will take that lively puppylike behaviour right into adulthood.

Physical vs emotional maturity

Now we know about how quick a dog can physically grow, let’s talk about their emotional maturity. This is a completely different matter altogether.

Most puppies will grow up a lot quicker physically than they do mentally, some don’t leave the puppy stage for a very long time – sorry to break that news to you!

Typically, a dog stops being a puppy emotionally between 1 year and 18 months old, but this again varies from dog to dog. Larger breeds usually retain their puppylike manners for much longer.

Everyday you might wake up and hope that your puppy has grown up, you’re exhausted with the constant mischief, liveliness and need for attention. However, growing up happens slowly over a long period of time. Here are some signs to look out for that indicate your puppy may be growing up:

  • Your pup is happy to relax alone and doesn’t demand (quite) as much attention from you anymore

  • Puppy biting and mouthing will subside

  • Previously, your puppy might’ve been partial to destroying and chewing things, keep an eye out for less damaged furniture

  • More capable of restraining themselves

  • More responsive to you and your training

  • Beginning to understand social cues from other dogs

  • Settles down a lot quicker

Overall, there really isn’t a definite way to tell how long your puppy will take to grow up, it’s different from one dog to the next. Knowing the standard size of your breed is the best way to tell how big your puppy will end up and in turn, how long it’ll take for them to reach that size.

Just be aware, even if your puppy is fully grown, don’t expect them to stop acting like a puppy for a very long time!