The early stages of growth and development for any puppy are important. Chihuahuas are the smallest breed, so their growth is at the tip of the extreme – at the tiny end of the scale.
This guide tells you everything you need to know about the normal growth and development of a chihuahua puppy from 0 to 12 months – with pointers to help you train your pup.
It’s important to remember there is variation between individuals, this is only a guide. It’s best to have regular health and weight checks with your veterinarian to double-check that your pup is developing appropriately.
Chihuahuas Breed Overview
They grew in popularity in the late 1800s. The modern breed derives from a cross between a small Mexican dog called the Techichi and an Asian breed brought to South America via the Bering Strait. The smallest recorded dog is a Chihuahua called Miracle Milly. She was only 3.8” tall. Most Chihuahuas reach around 6” in height, which is pretty mini – but the size of their personality is definitely massive.
Chihuahuas are a fun-loving and feisty breed. They are known for their domed heads, pricked ears, and alert expression. Chihuahuas love company, so if you’re home a lot and love playtime and cuddles, you could be perfect partners. It’s important that Chihuahuas are still treated like dogs – just because they’re small doesn’t necessarily mean they enjoy being in handbags – they need plenty of activity.
Chihuahua Varieties
The only Kennel Club-recognized varieties of Chihuahua are long and short-coated. These show no difference in their expected weight or height. But long-haired Chis are more prone to shedding. Unofficially, ‘apple head’ and ‘deer head’ variations are discussed, where deer-headed are said to be bigger.
People also talk of teacup Chihuahuas. These are not officially recognized – they’re just Chihuahuas – but Chihuahuas can be very small. While different-sized Chihuahua varieties are not officially recognized, genetics play a large part in how large a Chihuahua grows. There’s a lot of variation between fully grown adults, who can weigh between 2lb and 7lb. Big parents are likely to lead to bigger pups, but not always.
Why Is A Growth Chart Important?
Purebred Chihuahuas, just like many other purebred dogs, are linked to certain health conditions (crossbreds can inherit diseases too). While the Chi is a healthy breed overall, there are a few breed-linked issues that can show up in early life. Recognizing signs like stunted growth, poor muscle development, or a pup being less active than expected can help your pup get an early diagnosis and treatment.
Obesity is also a disease, and becoming overweight in puppyhood can make adult obesity more likely.
Why Is Training & Social Development Important?
Socialization is teaching dogs the skills they need to feel happy and confident in their environment. This includes learning how to mix with other dogs, other animals, and people. Dogs need to learn communication skills, acceptance, and tolerance – just like we do.
Chihuahuas are courageous and extremely loyal while also having an independent streak. These traits are great – but can lead to behavioral issues if not handled correctly in puppyhood. Chihuahuas can be defensive and snappy if not well-socialized.
Training
Training should be positive and encouraging. Reward the behavior you want in your pup with fuss, an encouraging word, a game, or a treat. Never punish unwanted behavior. Distract your pup instead. For further information on training and socialization, speak to your veterinarian. They will be able to advise you, and they may recommend training classes to help get the maximum benefit during the crucial first months of your pup’s life.
Growth Chart
In general, your pet should stay around the same level in the weight range. In other words, if your chihuahua puppy is born very small and is at the lower end of the weight range, they’re likely to stay at the lower end of the weight range for each stage and be a small adult.
On the other hand, if you have a large puppy, they are likely to be a large adult, so you should take the upper end of the weight range. Male and female chihuahuas are similar in size, so we have not included separate sizes for them here.
| Age | Height | Weight |
|---|---|---|
| 1 month | N/A | 9-20 ounces |
| 2 months | 2-4 inches | 1-2 lbs |
| 3 months | 2.5-4.5 inches | 1.5-2.5 lbs |
| 4 months | 3-5 inches | 2-4 lbs |
| 5 months | 4-5.5 inches | 2-4 lbs |
| 6 months | 4.5-6 inches | 2.5-4.5 lbs |
| 7-10 months | 5-7 inches | 2.5-6 lbs |
| 12+ months | 6-10 inches | 2.5-7 lbs |
0 – 1 month
Estimated Weight: Approximately 3-6 Ounces
New-born Chihuahua pups are vulnerable to cold. Chi pups have what is known as a large ‘surface area to volume ratio’ – there’s a lot of skin for their tiny amount of body mass – so they lose heat easily. Mom and pups should be kept in a warm environment.
Nurturing Moms will provide pups with all the nutrition they need, providing her milk is plentiful. Speak with your veterinarian about how to feed a bitch with pups.
To start with, the puppies’ eyes are closed, and they move very little. You hear tiny squeaks as they scramble to get to Mom’s milk. As the month goes on, the pups will open their eyes and become more active, learning very early social skills with their littermates.
1 Month
Estimated Weight: Approximately 9-20 Ounces
Pups will learn to explore their environment more, getting bolder and rapidly gaining weight. Weight gain helps them to control their body temperature better, but they still need to be kept warm with their mom.
Pups start learning skills to survive without their Mom, including learning to eat solid food. Offer the pups small amounts of puppy food – they’ll still be taking milk from mom too.
At this stage, most learning is from their Mom and littermates, although you can get pups used to being handled gently and playing with you too.
2 Months
Estimated Weight: Approximately 1 – 2 lbs
Pups become more independent – they’ve stopped drinking milk and often move to new homes. Pups should visit the veterinarian for health checks and vaccinations.
If you’re welcoming a puppy into your home for the first time, give your new pal lots of reassurance. Have familiar-smelling items around – keeping a blanket or soft toy that smells of the breeder’s home can be a comfort.
Pups should be fed 3-4 meals a day at this age. They only have small tummies. It’s a good idea to feed your Chi the same brand and flavor of food he was enjoying at the breeder’s home, so he doesn’t get a tummy upset while he’s settling in with you.
You can start basic training as soon as your puppy moves in. Start rewarding things like being responsive to your voice, being calm, and toileting in the right place. You can carry your Chi out and about so he can have a variety of experiences even though he’s not yet fully vaccinated.
Make sure he has plenty of playtime on the ground in your home or garden, too – Chi pups are no less active than larger breeds.
3 Months
Estimated Weight: Approximately 1.5 – 2.5 lbs
Your chi pup will still need 3-4 meals per day and will continue to grow. If you wish to change your chi onto a different food from what the breeder was giving, now is a good time. Make the transition gradually, over several days to a week.
Your pup should have had a second visit to the veterinarian for vaccinations. Then you can start going out for walks and leash training.
4 Months
Estimated Weight: Approximately 2-4lb
Mealtimes should be 3 times a day minimum. The food should be nutritionally balanced for puppies and bite-sized for your Chi’s tiny mouth. Dry food needs to be a mini kibble size.
Your Chi will become more boisterous at this age. Make sure you provide a safe environment for him to play in – away from objects he can pull down or places he could fall.
Exercise and play are vital for development, but they must be in moderation. Limit playtime and walks to 20 minutes, with rest in between.
Teaching your pup to be alone and rest quietly in between playtimes is important too
5 Months
Estimated Weight: Approximately 2-4 lbs
Pups should remain on puppy food and be eating 3 meals a day.
Chi pups can enjoy play and exercise in 25min chunks now, with rest in between.
Separation anxiety is common in Chihuahuas, so make sure you build your pup’s confidence in his own company. Make sure any children in the house understand that when Pup is resting, he must be left alone. Overtired dogs get fed up just like overtired children. Not being allowed to rest can be a reason for unwanted behaviors.
6 Months
Estimated Weight: Approximately 2.5 – 4.5 lbs
At this age, you can reduce your Chi’s meals to twice daily. Feeding more often into later puppyhood and adulthood is fine as long as daily calories are not excessive.
Pups can start to enjoy chews from 6 months onward. Make sure you choose chews that are puppy-appropriate and suitable for your Chi’s tiny mouth. Never leave your pup unattended with a chew.
This is a good time to visit your veterinarian. Your vet will check your pup’s body condition and ensure they’re growing appropriately.
Your vet can check if your pup’s teeth are developing correctly – retained or displaced teeth can be a problem in Chihuahuas.
The vet can also check for luxating patellae (kneecaps moving out of place). This condition is common in small breeds, and early diagnosis is helpful. Sometimes just altering the type of exercise that you’re doing with your pup can build up muscle to stabilize mild patella problems.
Your vet can also talk to you about when to neuter or spay your Chi and make sure your pup’s testicles have descended correctly (boys only).
7-10 Months
Estimated Weight: Approximately 2.5-6 lbs
Chihuahuas continue to develop their interest in the world, their playfulness, and their social skills between the ages of 7 and 10 months. Your pup will probably still gain weight but less rapidly than before. Chihuahuas usually reach mature weight by 10 months.
Chihuahuas can make the change from puppy to adult food during this time. Always remember to introduce the adult food slowly, over a week, gradually increasing the adult food and reducing the puppy food simultaneously. Keep having weight checks with your veterinarian to ensure any diet changes have not affected your pup’s body condition.
Your Chi may be fully grown but will still show puppy-like behaviors. Keep up with a consistent approach to training alongside relaxing playtime. Your pup can enjoy 35-40mins exercise at a time now.
10-12 months
Adult Weight: Approximately 2.5-7 lbs
Your pup is fully grown and full of character. Hopefully, your consistent, patient, and positive training has given your pup the perfect start in life. Your pup will be a balanced little sole, happy in a range of situations if your socialization has gone well. You’ll be able to enjoy lots of experiences together.
When you see your veterinarian for booster vaccinations so you can check your Chi’s stable adult weight. If you do have any questions about your pup’s health or behavior as you transition to owning an adult dog, this is a great time to ask.
Final Thoughts
Chihuahuas are generally healthy dogs, but they are prone to certain health problems such as dental issues, luxating patella, and heart problems. Proper care and regular veterinary checkups can help ensure a long and healthy life for your Chihuahua.
As with all dogs, their lifespan can be affected by various factors such as genetics, diet, exercise, and overall care. Providing your Chihuahua with a nutritious diet, regular exercise, and proper veterinary care can help them live a happy and prosperous life for many years.
I would love to have a chihuahua