The Chihuahua is a small breed of dog, typically weighing between 3 to 6 lbs. Is it possible to know a Chihuahua dog’s full grown size based on how small they are as a puppy? Not really, only an estimation can be given. The truth is, because of genetics, it’s possible that two medium-sized Chihuahuas can have puppies in a wide range of sizes.

Whether a Chihuahua is a full grown dog or a tiny puppy, its size cannot be determined just by looking at their height, length, or weight alone. You have to put all of these factors together to get the full picture of a dog’s general size and body structure. Let’s go over a few true real life examples on size:

Chihuahua size chart

Chihuahua Dog Size: Two Examples

First Example: Several years ago, a woman named Billie contacted me over a very sick “teacup” puppy she had just picked up at the airport. She picked this puppy up from a breeder in Texas. After searching online, she ended up calling me.

The puppy she had bought from the Texas breeder had bloody diarrhea. She noticed the puppy was only 16 ounces; it was thin and its ribs were showing. In inches, the puppy was the size of an adult Chihuahua. So what was the problem? Hookworms had not allowed the puppy to gain weight, but the body skeleton length was similar to my ADULTS. Imagine a breeder calling a puppy a “teacup” solely due to extreme low weight! The puppy ended up 11 lbs as an adult. 

Second Example: As mentioned earlier, Billie noticed the puppy she had bought from Texas was not a smaller Chihuahua. Rather, it was a severely malnourished and grossly underweight, even skeletal. The puppy gained 4 lbs. in just eight weeks. Imagine that! A pound every 14 days!

As Billie and I got to be acquainted with each other, she asked to buy my “Stuart” who I had listed as charting “4.5 lbs. grown.” At nine weeks old, Stuart was 2 lbs. After Billie received the puppy, some time went by. Stuart was now one year old, but he was still 2 lbs. How was that possible? I insisted that Billie put him on a diet to GAIN weight, but after a few weeks of the customer following my advise to fatten Stuart up, he only gained 1 ounce. So this Chihuahua was truly a 2 lbs. size fully grown. Obviously when it came to my adult size estimation, I made an error.

What Happened To My Chihuahua Size Estimation?

I estimated that this puppy would 4.5 lbs. grown, but he turned out to be 2 lbs. instead. So what went wrong?

It’s because Stuart was a hefty overweight Chihuahua puppy at nine weeks. Most of my puppies around that age are 1 pound or less, but he was twice that. I made my estimation based on only on his body weight, when I should have been paying more attention to his body inch measurement, since his size was very small. It was a simple mistake, but it was one that helped me to learn more about Chihuahua dog sizes.

Chihuahua Puppy Info: Ears, Canned Food, Molera

When it comes to the ears of a Chihuahua, they normally tip. It’s normal for the ears of a puppy to go up and down while they are teething up to 6 months of age. Below is a photo of Bug as a puppy, and then one of her as an adult dog.

Canned Food Is Dangerous to Puppies

Do not use canned dog or puppy foods to feed your Chihuahua puppy. It’s extremely dangerous for tiny puppies. When I say canned food, I mean all soft dogs foods, including the ones in the plastic containers and foil pouches. Although bacteria are killed during the canning process, the “toxic poop”(endotoxins) made by the bacteria remain. So while high heat is used in the canning process to kill bacteria, this does not destroy the endotoxins.

Is Molera Normal In Chihuahuas? 

Soft spot on top of head, usually smaller then a dime, similar to the fontanel newborn human have. In the past, molera was accepted as a mark of purity in the breed. It is mentioned as a Chihuahua breed standards around the world. It’s presence is normal in the applehead Chihuahua puppies.

Unfortunately, some people, including ignorant veterinarians who are not familiar with the Chihuahua dog breed, have tried to link the mere presence of a molera with brain defects. Imagine if human doctors did that to the parents regarding human babies soft spots! Some incompetent vets will say the puppy has a “hole in its head” and needs a neurologist immediately, but this is inaccurate. If your vet is so unfamiliar with Chihuahuas so as not to know about Moleras, you should probably switch to a more knowledgeable veterinarian. Such Ignorant remarks scare owners, causing unnecessary distress.

If your puppy has a larger molera, try to prevent them from going under the bed or under wood furniture. Why is that? Because if they hit the top of their head where the soft spot is, that can cause injury. The closing of the molera usually happens by one year to 14 months in most applehead Chihuahuas.