When Do Australian Shepherds STOP Growing? 

Australian Shepherds are an excellent dog to have as part of your family. They are highly intelligent, very active, love to please their owners, and do not get to be extremely large. But they are not tiny dogs.

So when do Australian Shepherds stop growing? 

when do Australian Shepherds stop growing
When do Australian Shepherds stop growing?

This helpful guide goes over the impacting factors of how big your Australian Shepherd gets and when you can expect them to stop growing. 

The Growth Cycle of an Australian Shepherd 

You may not realize it, but your Australian Shepherd will grow to its full height before reaching its total weight. Although this characteristic is common among dogs, smaller Australian Shepherds will generally stop growing sooner than standard-sized ones. 

A standard Australian Shepherd will generally reach their total height and weigh between 16 and 18 months. Alternatively, miniature variations will often stop growing by 12 to 16 months of age. 

Here is a more detailed breakdown of the growth cycle for a standard-size male Australian Shepherd from puppy to adult. 

Australian Shepherd Growth Chart (Male)

Weight RangeHeight Range (at Withers)
8 weeks5 to 7 lbs3” to 5”
9 weeks7 to 12 lbs5” to 8”
10 weeks15 to 18 lbs7” to 11”
11 weeks18 to 23 lbs9” to 12”
3 months21 to 27 lbs11” to 13”
4 months28 to 35 lbs12” to 14”
5 months34 to 43 lbs13” to 15”
6 months36 to 49 lbs15” to 17”
7 months44 to 55 lbs16” to 18”
8 months47 to 58 lbs17” to 19”
9 months49 to 63 lbs18” to 20”
10 months51 to 65 lbs19” to 21”
11 months54 to 67 lbs20” to 22”
1 year54 to 68 lbs20” to 23”
2 years56 to 69 lbs20” to 23”

This table details the puppy to adult growth cycle for a standard-size female Australian Shepherd

Best Dog Food or Australian Shepherds

Australian Shepherd Growth Chart (Female)

Weight RangeHeight Range (at Withers)
8 weeks4 to 8 lbs3” to 5”
9 weeks6 to 11 lbs5” to 8”
10 weeks10 to 15 lbs7” to 11”
11 weeks12 to 20 lbs9” to 12”
3 months14 to 21 lbs11” to 13”
4 months19 to 28 lbs11” to 14”
5 months24 to 35 lbs12” to 14”
6 months26 to 39 lbs13” to 15”
7 months29 to 44 lbs14” to 16”
8 months31 to 47 lbs15” to 17”
9 months33 to 49 lbs16” to 18”
10 months34 to 51 lbs17” to 18”
11 months35 to 52 lbs18” to 20”
1 year36 to 54 lbs18” to 21”
2 years37 to 55 lbs18” to 21”

Dog lovers can typically expect their Australian Shepherd to stop growing between the ages of one and two years. Although your four-legged friend may reach their total height at 12 months, they usually take a bit more time to fill out and get to their final body weight. 

It is obvious how quickly this breed grows in the first eight or nine months, but it begins to slow down near this time. So although your Australian Shepherd still has growing to do, it will be less rapid than their puppy stage. 

However, some crucial elements can affect the growth rates and adult size.  

The Average Australian Shepherd Size 

The average Australian Shepherd is a medium-sized dog that is a perfect companion on those long hikes or as an adventure buddy. However, some breeders offer miniature Australian Shepherds, providing a more compact version of this lovable dog. 

mini Australian shepherd dogs
A Mini Australian Shepherd is a lively and athletic small dog

For comparison, the average fully-grown Australian Shepherds measure: 

Standard Males: 

  • Height at withers: 20” to 23”
  • Length: 31” to 36”
  • Weight: 55 to 70 lbs (25 to 32 kg)

Standard Females: 

  • Height at withers: 18” to 21”
  • Length: 28” to 31”
  • Weight: 33 to 55 lbs (16 to 25 kg)

Miniature Males: 

  • Height at withers: 14” to 18”
  • Length: 20” to 28”
  • Weight: 20 to 40 lbs (9 to 18 kg)

Miniature Females: 

  • Height at withers: 13” to 17”
  • Length: 20” to 28”
  • Weight: 20 to 40 lbs (9 to 18 kg)

However, some elements will alter how big your four-legged friend gets. Some factors that help determine the size of an Australian Shepherd include: 

  • Sex
  • Age
  • Genetics 
  • Activity level 
  • Breed


Naturally, male and female dogs can vary in size, with the males averaging slightly larger. In addition, Australian Shepherds that undergo spay or neuter surgery tend to weigh more due to a decrease in hormones. 

Alternatively, some may argue that if a dog is spayed or neutered too early, it could hinder its growth, making them a more petite adult. However, there is yet to be significant data to support this claim, and many dogs undergo this sterilization surgery well before their sexual maturity without ill effects. 


The age of your dog will indicate its average size. For example, an Australian Shepherd that’s around five months old should be half of their grown weight and height. Doubling their measurements at 20 weeks will provide a reasonable estimate of their final size as adults. 


Like other animals, genetics come into play when examining how big an Australian Shepherd will get. Dogs with larger or smaller parents are more likely to take on those traits, keeping them smaller or larger than average. 

Genetics can also determine if your Aussie will face health problems that could interfere with their body weight. For example, some animals will have ailments, such as Cushing’s Disease or hypothyroidism, resulting in your dog weighing more than one with a clean bill of health. 

Activity Level 

The activity level of your Australian Shepherd may not alter how tall they grow, but it will affect how much they weigh. This breed is highly active and intelligent, making them medium to high-energy dogs that require ample exercise with a proper diet

Thankfully, this activity level keeps Australian Shepherds relatively lean and fit. However, remember that an active dog should receive a healthy, balanced diet, and if they are not exercising enough, too many high-calorie foods and treats will make them gain weight

an older Aussie shepherd
An older Australian Shepherd


Although you may choose an Australian Shepherd for your next pet, it may not be purebred. Unless you have certification from a breeder of its bloodlines and breeding stock, there is a chance it could be a mixed breed.

While mixed breeds are still terrific animals to own and crossing an Aussie with another dog breed does not pose any problems, this element can affect their growth. 

For example, if your dog has a parent smaller in stature than a standard Australian Shepherd, they may stop growing around the 12-month mark and remain on the small side.

Conversely, dogs who come from a mix with a larger breed, such as a Labrador or Mastiff, may continue to grow well past the 16-month mark and be overly large compared to a standard Australian Shepherd. 

If My Australian Shepherd Is Smaller Than Normal or Seems To Stop Growing, Is Something Wrong?

Dogs are unique, much like people. They may carry their parent’s traits or differ from them. Therefore, guessing the size of your Australian Shepherd and when they stop growing is not an exact science. 

Some dogs will stop growing earlier than others, around the 16-month mark, while others may continue growing until they reach two years of age. If your dog is not exhibiting any other health concerns, there is usually nothing to worry about. 

However, dogs that stop growing extremely early or seem to have stunted growth should see a qualified veterinarian for a complete exam. This professional can rule out any genetic disorders or problems that may interfere with your pet’s growth and development. 

running Australian shepherd
A running Australian Shepherd

So, When Do Australian Shepherds Stop Growing 

The Australian Shepherd is a terrific dog to have by your side at home or while on an adventure. Knowing how big it will get and when Australian Shepherds stop growing will help you prepare for your new pet and keep them healthy and happy while living with you. 

Dog lovers can expect their Australian Shepherd to stop growing around 16 to 18 months old, as they will reach their final height around 12 months and finish filling out before they turn two. Once your pet is two years old, it will be fully grown and should not grow any further.