Shih Tzu Age Stages & Info

Shih Tzu dogs at different ages
Shih Tzu dogs different ages

In this Article:

Shih Tzu Ages and Stages - Just to start things off, a quick summary of the terms that describe each age group with the Shih Tzu breed. 

Shih Tzu Milestones - Points to note through the first year which is filled with developments, and beyond.

Shih Tzu Age Equivalency Chart - A simple but accurate look at a Shih Tzu's age in comparison to human years. With small dogs, it is a bit different than the general '1 year equals 7 years'.

Shih Tzu Though the Ages: Behavior, Activity and Care - An overview of how Shih Tzu puppies, adults and seniors compare in regard to activity, behavior, sleep requirements, and nutrition. 

Related Articles:

Jump Below to Read About: Age Progression Photos, Life Span, Oldest Living Shih Tzu Dogs and Senior Shih Tzu Care

Shih Tzu Ages and Stages

There are 2 main phases of aging and developmental stages for Shih Tzu, along with subcategories: 
Puppy - This includes newborn (birth to 3 weeks old) and puppy (4 weeks old to 11 months old) which can be further divided into young puppy (4 weeks old to 4 months old) and older puppy (5 months old to 11 months old).

Adult - Shih Tzu dogs become adults at the 1 year mark. The adult stage can be further divided into adult (1 year to 9 years old) and senior (10 years old and up). 

Shih Tzu Age Milestones

Birth: Brand newborn puppies have developing nervous systems and only basic reflexes of burrowing, suckling, a perineal reflex for having urination and defecation triggered, and a carrying reflex in which the pup tenses if carried by the scruff. Eye lids are closed tight and ear canals are closed, so pups cannot see or hear. 

2 weeks old: Eyelids are beginning to open. Ear canals are opening and hearing is starting to come in. For some 'early bloomers', milk teeth may start erupting. Tails are wagging. The 2-week-old is crawling and may make some wobbly short-lived attempts at walking. 
Shih Tzu puppy at 2 weeks old
Two week old Mochi, photo courtesy of Janet Perello
3 weeks old: Puppies can hear much better now and eyes are now fully open yet hearing and sight are not yet fully developed. Pups are becoming more active and able to walk around, typically having mastered the skill in just three days or less. Vocalization may begin; this will sound like ‘peeps’ and ‘squeaks’. 

4 weeks old: Puppies at this age can begin to venture out of the whelping box for supervised exploration. Play between littermates can be quite animated. Vocalizations will continue and grow stronger. Milk teeth are erupting and weaning (transition to solid food) begins. The socialization phase starts; tolerance and fears start to become established. Emotional attachments start to be made and bonds develop. 

6 weeks old: Weaning should be complete at this age. Sight and hearing are fully developed. Puppies are very curious and continue to explore their immediate world. 

2 months old: Puppies are often ready to transition to their new homes. At this age, pups can be easily startled, but fears are not fully set into place. Socialization continues. Free-feeding is done at this time. House training lessons can start to be understood. 
3 months old: This is the beginning of the ‘ranking phase’ in which a puppy starts to learn their place within the hierarchy of the household (within the den [house] there is an alpha [leader] that rules over the pack [all others, both human and animal]). So, this is the age you want to set rules and make your leadership clear.

A pup should now be eating 3 daily scheduled meals per day, plus snacks. Daily exercise, via walks, allows for further building of socialization skills. 
Shih Tzu puppy at 3 months old
Zeus, at 13 weeks old, photo courtesy of Lisa Oliveira
4 months old: The ‘ranking phase’ is still underway and lessons are being learned. The puppy is now much more aware of their surroundings. Some fears may have set in. At this age, a pup may protest being left alone more so than when he was younger; separation anxiety issues may develop or grow stronger. House training is nearly complete. Teething begins. Energy levels are high. 
6 months old: This is the beginning of the adolescent stage and puberty is underway for both genders. If not spayed, females have just had or will have their first heat. Pups at this age fully understand the household's hierarchy and how their behavior affects their 'pack mates' (humans and any other animals in the house). 

It is at this age that a Shih Tzu may start to challenge the ranking (particularly if they sense any wavering or weakness); you can stand firm in your place as leader by expecting a 'sit' before any meals or snacks are given. Also at this age, teething may be winding down somewhat and once super-hyper puppies are becoming calmer, so things may be less chaotic. Physical growth is slowing down.

9 months old: Growth has noticeably slowed. Some Shih Tzu puppies will stop growing by the age of 9, 10 or 11-months old. For others, there will be a small gain from now until 12 to 15-months. Teething is complete for most pups.
1 year old: A Shih Tzu is deemed an adult. Most adult Shih Tzu are alert, active, and want to be kept engaged, but also do well resting and relaxing with their family. Adult weight and height are just about set at this time. The coat can grow quite long now (floor length is generally possible by the 15 to 24-month mark). 
Shih Tzu at 1 year old
Emmie Lou at 16 months old, photo courtesy of Patti
1 year through 9 years old: A Shih Tzu is in his or her prime. They have calmed down from their puppy stage but are still very active and engaging. 
 
10+ years old: There is no official age that a dog is declared to be a senior; this is usually based on overall lifespan and size grouping (toy breeds become seniors later than large breeds). Though some veterinarians may declare it earlier, most deem a Shih Tzu to be a senior by the 10-year mark. 
Shih Tzu senior dog at 11 years old
Abbey, happy as ever at 11 years old, photo courtesy of Ralph

Shih Tzu Age Equivalency Chart

The idea that a dog ages 7 years for every human year is a broad generalization that was based on the estimate that a human lived to the age of 70. Dogs actually age at different rates. Size (toy breed vs large breed) is a major determining factor. Overall, smaller dogs live longer and thus age slower than larger dogs. 

And for canines of all sizes, the aging process is very rapid over the first two years and then things slow down and even out (this is why puberty happens around the 6-month mark for toy breeds which is not the 3.5 year mark as the '7 years = 1 year' rule would imply).

So, keeping that in mind, let's take a look at the age your Shih Tzu is in human years: 
Shih Tzu Age    Human Age 
6 months            5 years
1                       15
2                       30
3                       34
4                       38
5                       42
6                       46
7                       50
8                       54
9                       58
10                     62
11                     66
12                     70
13                     74
14                     78
15                     82
16                     86

Shih Tzu Through the Ages: Behavior, Activity, and Care

Activity Levels: From Energetic Puppies to Mellow Seniors


Puppies are balls of energy. They require regular playtime and frequent short walks. This stage is vital for their physical development and social skills. Adult Shih Tzu dogs have a noticeable reduction in energy levels compared to their younger selves. While still playful, they need a balanced routine of exercise and rest. In contrast, senior Shih Tzu dogs experience a significant decline in activity. They tend to be more sedentary, requiring gentle exercise to maintain muscle strength and overall health.

Behavior: Maturing Over Time


Shih Tzu puppies often display boundless curiosity and playfulness, which can translate into mischievous behavior. Training and socialization are crucial at this stage. As adults, the Shih Tzu generally exhibits a more balanced temperament, showing a mix of playful and calm behaviors. They enjoy learning and need mental stimulation. In their senior years, these dogs may show signs of cognitive decline, such as disorientation or changes in behavior. They might also become more irritable or anxious, especially if experiencing discomfort due to health issues.

Sleep Requirements: Changing Needs


Shih Tzu puppies, similar to human infants, require a lot of sleep. This is essential for their growth and development. They may sleep up to 18-20 hours a day, interspersed with bouts of high energy. As they mature into adulthood, their sleep needs decrease, stabilizing at around 12-14 hours a day, including naps. However, as they progress into their senior years, they tend to sleep more again, akin to their puppy days, but this time due to a decrease in energy and potential health issues.

Health and Nutritional Needs: Adapting to Each Life Stage


Puppies have specific nutritional needs to support their rapid growth and development. They require a diet rich in proteins and fats, along with essential vitamins and minerals. Health-wise, they are vulnerable to puppy-specific conditions and require regular vaccinations and check-ups.


Adult Shih Tzu dogs need a balanced diet that supports their less active lifestyle compared to their puppy stage. Adult dogs can be prone to obesity, so monitoring their food intake and ensuring they get the right balance of nutrients is key. Regular health checks are important to monitor for breed-specific issues like dental problems and eye diseases.


Senior Shih Tzu dogs often require diets that cater to lower energy levels and specific health issues, like joint problems or heart disease. They may need food that is easier to digest and lower in calories but still nutritionally complete. Health monitoring in seniors should be more frequent, focusing on managing chronic conditions and ensuring their comfort in the later stages of life.

Shih Tzu Age Progression Photos Puppy to Adult - The ways in which a Shih Tzu physically changes as they mature and some interesting photos of Shih Tzu as young puppies and then as gorgeous adults.

Shih Tzu Growth Chart - The speed at which this breed grows and our estimates regarding the final adult size of puppies. While this is just an estimation, it can give you a good idea of what to expect. 

Shih Tzu Life Span - How long the Shih Tzu breed lives on average, comparison to other small dogs, and steps you can take to help your little guy or gal live a long life.

Oldest Living Shih Tzu Dogs - A summary of the oldest dogs ever to have lived, and the oldest Shih Tzu that we have personally verified.

Senior Shih Tzu Dogs - A complete guide to taking care of the senior Shih Tzu. Changes to make in advance, tasks that require adjustments and ways to help keep your guy or gal happy and healthy in their golden years.

More Articles:

The Best Toys for a Shih Tzu - Whether you have a rambunctious teething pup, a bored adult or a senior that needs some motivation, see which types of toys can be beneficial to your Shih Tzu, along with our top recommendations.

Shih Tzu Grooming Tools - If you're wondering what are the best combs, brushes, and other grooming tools you should have for your little guy or gal, this is the place. We cover all necessary grooming items to take great care of your Shih Tzu.

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