Dog Training

When is a dog full grown? (All growth phases)

Have you also asked yourself: When is my dog actually fully grown? How long does it grow and what should I pay attention to? Then you are right here, I show you everything important on this subject.

Puppy Bite Inhibition Play
Table of contents

The main growth phase of your dog is the third to seventh month. This phase is particularly important for the development of your dog. A suitable diet from an early age is essential for optimal growth.

Difference of size with growth

Breeds from small to large

You have to four sizes or weight classes distinguish from dogs: 

  • Small
  • Medium size
  • Large
  • Very large

There is a relationship between the size of the dog breed and growth. Small dog breeds are born significantly heavier than large breeds in relation to their final weight. 

While smaller dogs increase their weight twenty-five times during the growth phase, in large dogs it is even a hundred times. 

The growth period also changes according to the size. For small dogs it is ten months, for very large - two years. 

The final body size of a dog is genetically predetermined. Therefore, you cannot influence the final size of a dog through excessive nutrition. 

While you can use it to speed up the growth rate, you can't use it to speed up the end result. Besides, it is not healthy for your dog. 

As a dog owner, it should be important to you that your dog grows out at a healthy rate. Healthy growth is relatively slow growth.

Growth period

Since dogs have a growth period of mostly one year, special attention must be paid to rearing and feeding. So there is not much time to correct rearing errors with physical impairments. 

The most rapid weight gain occurs between the third and sixth month of life. Your dog's body is challenged the most during this period. Careful nutrition and husbandry is most important here.

The development of body weight can be measured approximately like this: For small breeds after six months are reached about 70% of the final weight or size, for very large a little less. This is usually a good estimate of whether the growth of your pet is optimal.

Breed size Approximate growing time
Small Until 10 months
Medium size Until 12 months
Large Until 18 months
Very large Until 24 months

The growth phases

Growth dog

Nevertheless, the stages of growth are the same for all breeds of dogs. Each puppy goes through the following seven stages of development after birth:

Week 1 to 2: The Neonatal Phase

While the sense of smell is already well developed, the eyes and external auditory canals are still closed during the first two weeks after birth. 

Puppies can still find the milk teats without any problems. The warmth of the mother and the sense of smell help your puppy. Almost the whole day he spends sleeping and drinking the mother's milk. 

He cannot yet regulate his own body temperature and should therefore always be kept warm.

Week 3: The transition phase

Eyes and hearing are no longer closed, so your puppy can now see and hear. He begins to move and perceive his surroundings. His siblings also move into his awareness. He starts to teethe.

Week 4 to 7: The imprinting phase

Your puppy's curiosity is growing steadily. He devotes himself increasingly to his environment. In this phase you can already recognize the future temperament. 

You must not leave your puppy alone, as contact with people and with his littermates is of great importance.

Week 8 to 12: The socialization phase

This phase shapes your dog's future social behavior. It is important that he gets to know his environment well without overtaxing him. 

Coping with the unknown is an important part of development. The self-confidence of your puppy is an important prerequisite for the later harmony between you and your darling.

Month 3 to 6: The ranking and pack order phase

Your four-legged friend must now settle into your "pack". It is up to you to show him boundaries. Only through clear and understandable rules can your dog recognize a hierarchy and find his position. 

Here you should deal with your new family member lovingly, but also consistently.

Month 7 to 12: The pubertal phase

Dogs also have a "defiant phase". In parallel, a bitch comes into heat for the first time during this phase and a male dog feels the urge to reproduce. 

Your dog will try to test his limits. You will have the feeling that he has forgotten what he has learned. Your patience is needed at this stage. 

You should definitely be caring but consistent with your pet. 

Monat 12 to 30: The maturity phase

The last phase is the transition from puppy to adult dog. Growth is now complete, but note that your dog never stops learning. 

Especially in this phase, a close bond to promote trust between you is very important. Keep your pet busy and stimulated - physically and mentally.

What do you need to keep in mind during the growth phase?

In the beginning, of course, the medical care of your pet is in the foreground. This begins with the first vaccinations and is your responsibility. The veterinarian you trust can best advise you on this.

Nutrition is the key to an optimal growth phase. For the proper development of your puppy, you must take into account certain food needs. 

By nature, the maternal instinct ensures that the puppies get the right dosage of food. The composition is also optimized by the mother. Unfortunately, due to the early weaning of the puppies, the responsibility lies first with the breeder and then with you.

These are the three points you should keep in mind when feeding

1. weigh the correct amount of feed!

On food packages are given recommendations on food quantity, but the correct amount may vary per dog. 

You should weigh the amount before feeding. This is the only way to avoid overfeeding. Keep in mind that it is better to feed a little less. 

This way you avoid a too fast growth. If you want to give your puppy treats in addition to the normal food ration, you must include them in the daily food ration. 

If your puppy is of a large or very large breed, you can use the Take the growth curve of this breed to help. So you can better control the daily weight gain.

2. avoid over- and undersupply!

If you give your puppy ready-made food, you should special puppy food buy. Here you already have the right composition of nutrients. Additives are no longer necessary. The calcium requirement is also already in the right ratio. 

If you prefer BARF, you should seek advice from a professional regarding ingredients. You should also ask for the ration size per month. In the growth phase it is very important to avoid over- or undersupply.

Two major mistakes in particular are made during the development phase:

  • Overfeeding
  • Calcium intake too high

Too rapid growth between the third and sixth month leads to growth-related skeletal disorders. Since circulation and musculature cannot keep up with skeletal development, a mismatch occurs. 

In the next two to four months, the first consequential damage becomes apparent. Here, for example, it can lead to Misalignments of the front legs, lameness or joint restrictions may occur. 

3. pay attention to the correct amount of calcium!

Excessive calcium intake leads to bone and cartilage remodeling disorders, i.e. bone and cartilage thicken. The insufficient supply to the thickened tissue results in the detachment of pieces of cartilage, the so-called Osteochondrosis

The body regulates calcium absorption through vitamin D. However, this only occurs after the fifth month. Feeding calcium (e.g. with bone meal) in high amounts before this month leads to unlimited absorption.

The right movement

Puppy step stairs

Not only does proper nutrition play a role in the growth phase, but so does exercise. Through the optimal movement and load according to age, joints and muscles are developed. 

Pay attention to the appropriate activities for each stage of development. Walks and games should be adapted to each phase. Your puppy usually can not calm down by itself, because it overestimates its endurance. You need to provide rest breaks.

Your puppy should learn early enough to climb up and down stairs under supervision. Especially if you live in a Apartment reside. 

For many puppies, walking up and down stairs is a challenge at first, and it also comes with plenty of fear. Do not force your puppy to do this. You can encourage him with a treat or by giving him a loving pep talk. 

Make sure that he does not jump up and down several steps at once. You should also make sure that he does not have to climb up and down stairs too much during his development phase. The stairs should also be non-slip.

The adult dog

If you want your dog measure and weigh weekly, you can best keep an eye on its growth. Once his size doesn't change too much, the growth will gradually stop. You can expect it from the tenth month, depending on the breed size.

Of course, body weight is still important for adult dogs. Until the 18th month, the weight of your four-legged friend should always be at the lower limit. As soon as he is fully grown, he must not get overweight either. 

The easiest way to control this is through the ribs. If these are well palpable, there is no overweight. Keep a stable weight and weigh your dog regularly, even in adulthood.


Ultimately, the responsibility for a healthy dog life lies with you. The growth phase determines the entire later life of your favorite. Therefore, provide early enough for a proper diet, exercise and education. This is the only way to raise a physically and mentally fit dog.

Written by Claudia Weise
Written by Claudia Weise

I am an editor at hundeo and when it comes to dogs, my heart beats faster. My goal is to publish the best dog guides on the web. There is a lot of passion in every article and I am happy about every feedback to constantly improve our content.

Learn more

Share now:


  1. Hello!
    My dachshund is already 18.5 months old and still growing!!!
    I have known him since he was 2 weeks old and he was not the biggest in the litter.
    His mother weighs about half and his father is even smaller, though his grandmother is much taller than her daughter.
    He is my 1st little dog & I am very insecure v. a. because he grows even for me visibly, although I have him around me all the time.
    According to the owner of his mother and grandmother, this has never happened to any of their litters, including other dachshunds.

    I am very grateful for knowledge and experience!

    1. Mine from Hundeo

      Hello Robin, small breeds are usually full grown in about 12 months. Whether it is a disposition or a health problem with your dachshund, we can unfortunately not judge. It is best to ask your vet for advice.

    1. Enrico from Hundeo

      Hi. How big mixed breeds grow and how long they grow depends a lot on the crossbreed. So it would always be good to know what breeds are in it. It would also be interesting to know if it is a small or large breed. Maybe you also know the parents to be able to estimate this better?

  2. Hello, my collie dog is 13 months old and weighs 18.6 kilograms. Is this already too much? She was also hot the first time at 7 months and now again after 6 months. Because of the weight I am unsure. I don't know if this is ok.

    1. Natalie from Hundeo

      Dear Lydia, judging from your description, there is nothing to worry about with your collie dog. At 13 months, she has completed most of her physical growth. A weight of 18.6 kg is within a healthy range for Collies. Depending on how big she is, there may even be some room to go up.

      You don't have to worry about the heat either. Most bitches come into heat for the first time between 6 and 12 months and from then on twice a year. Here your bitch is also in the perfectly normal range.

  3. Hello, my dogo canario/American Bulldog will be 12 months old on 12/24, she weighs just under 30 Kg, she could be a little wider though. Is she done growing or is she still growing a bit in width?

    LG Christin

    1. Mine from Hundeo

      Dear Christin, large breeds usually complete their growth between 20 to 24 months of age. Your vet can certainly make a more accurate estimate for your mixed breed bitch.

  4. How do you define medium and large breeds, what are the classifications (in cm SH or/and KG)? Does a mixed breed (Austraian Shepherd-Spanish Water Dog mix) with 58cm and 24kg already count as "large"?

    1. Mine from Hundeo

      Hi Rosi, as a rough guideline you can say that dogs weighing up to 15 kg belong to the small breed, 15 to 45 kg body weight to the medium breed and more than 45 kg body weight to the large breed.

Leave a Reply

Your email address will not be published. Required fields are marked *