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How Big Is a Chihuahua Brain? (Read This First!)

Along with spaniels, pinschers, and terriers, chihuahuas are also very popular toy dogs. Toy dogs traditionally refer to very small breeds of dogs that have been intentionally bred down in size.

Along with being the smallest dog breed in the world, ranging between 5 to 8 inches in height, chihuahuas are also known for having the largest brains relative to their body.

How big is a chihuahua brain?

Although all breeds of dogs have a brain the size of a tangerine, chihuahuas are considered to have the biggest brain of all due to their ratio of brain to body size. The average weight of a chihuahua brain is 55.10 grams. Their intelligence makes them quick-witted and easy to train.

Average size chihuahua:

With Yorkshire terriers coming in second, chihuahuas take first place for being the smallest breed out of all dogs. An average size chihuahua’s height can be anywhere between 6 to 9 inches, and generally, weigh 2 to 5 pounds.

All dogs have a brain the size of a tangerine, or orange. Therefore, it does not possess numerous folds like a human’s brain or the capacity for higher thinking. However, chihuahuas are considered to have the largest brain out of all dog breeds in relation to body dimensions.

The mean weight of the average chihuahua’s brain is 55.10 grams, making them intelligent and willful dogs.

Teacup chihuahua:

Teacup chihuahuas are a variation of pure-bred chihuahuas that are smaller than average chihuahuas. They usually only grow to about 3 pounds and reach a height of 6 inches.

Although they are referred to as ‘micro’ or ‘teacup’, they are not exactly a separate breed of chihuahuas but are instead called this due to their tiny stature. 

Although teacup chihuahuas are considered highly intelligent and abiding, their brain size does not differ significantly from the average chihuahua (around 55.10 grams).

Teacup chihuahuas are rather energetic with quick-witted personalities, making mental stimulation a necessity to keep them entertained.

Deer head chihuahua:

Deer head chihuahuas are named as such due to their characteristic longer heads, necks, and necks as compared to their counterpart teacup chihuahuas. They are also generally bigger with larger ears.

Typically, deer head chihuahuas grow up to 8 to 12 inches in height and weigh an average of 10 pounds. Although they rarely exceed 12 pounds, this breed is still almost twice the size of apple head chihuahuas or teacup chihuahuas.

Although they are significantly much larger than the average chihuahua, deer heads possess the same size of the brain as other breeds of dogs. It is roughly 55 grams in weight and the size of an orange.

How much does a chihuahua brain weigh?

As with all breeds of dogs, chihuahuas also possess a brain roughly the size of a tangerine or large lemon. Their brains do not contain complex folds like human brains which limits their higher thinking capacity.

However, despite being the same size, chihuahuas are still considered to have the biggest brain out of all dog breeds. This is because of their high body-to-brain ratio as they have quite small bodies. In fact, they are the smallest breed among the entire canine kingdom.

Their brain generally weighs around 55.10 grams for all variations of breeds including the apple head, teacup, and deer head chihuahua. They are quick-witted and not difficult to train due to their intelligence.

Are chihuahuas’ brains bigger than their skulls?

Chihuahua’s brain certainly is not bigger than their skulls.

But around 85% to 90% of all breeds of chihuahuas are born with a ‘soft spot’ on their head, also known medically as a Molera. This anatomical feature can be found easily by gently running your index finger along the top center of their head.

It should feel like an opening in their skull several inches above the nose. It is caused by the parietal and frontal bones not having been fused together completely.

Although most puppies of all breeds are born with this feature, the cranial gap generally closes over time as they grow older. However, with many toy breeds such as chihuahuas, this may not be the case. In fact, the Molera may not ever close for some.

As chihuahuas were bred to be small with a weight between just 2 to 4 pounds, their dome-shaped skulls also shrunk in size with a tendency to retain a Molera. 

As deer head chihuahuas are typically twice as large as the average chihuahua, they are also less likely to form and retain a Molera while teacup chihuahuas are more likely to retain one.

Do chihuahuas have the biggest brain out of all dogs?

Despite being the smallest dog among the entire canine kingdom, chihuahuas still are considered to have the biggest brain out of all dogs. This is due to their high brain-to-body size ratio.

Their tiny stature is due to breeding them to be small, weighing just between 2 to 4 pounds. However, one side effect of this is the formation of an incomplete skull called a Molera. 8 out of 10 chihuahuas are born with a permanent cranial gap on the top center of their heads.

Although all dogs have roughly the same sized brain, chihuahuas have the largest brain relative to their body size, measuring an average of 55.10 grams.

The average canine has a brain with a mean weight of 72 grams, roughly the size of a tangerine or orange. The organ is mostly unwrinkled due to a lack of multiple folds such as in human brains, giving it a smoother surface.

Though this gives chihuahuas less opportunity for critical thinking, they are still decently intelligent. Despite not being at the top for intelligence, they are highly adaptive and quick-witted due to their alertness.

Do Chihuahuas have a high IQ? How smart are Chihuahuas compared to other dogs?

It is very difficult to standardize an IQ test on dogs due to the countless breeds and different motivators of each individual dog. While some may react better to treats, others may comply better with a favorite toy.

However, according to canine psychologist Stanley Coren, chihuahuas rank below average in terms of obedience intelligence.

During Coren’s Dog Intelligence Criteria, in which the judges measured how well various breeds performed in obedience tests, chihuahuas have ultimately labeled the 125th smartest dog breed out of 138 breeds that participated in the trials.

The IQ of a Chihuahua:

The chihuahuas were able to learn an unknown command within 40 to 80 repetitions, placing them in the “fair intelligence” category. On the other hand, the standard or average dog required just between 25 to 40 repetitions of a new command to fully learn it.

This required chihuahuas to spend almost double the amount of time to grasp and obey a new command as compared to “average dogs” such as the Siberian Husky, Great Dane, Havanese, and Australian shepherd.

Despite these comprehensive trials, many chihuahua owners disagree with Coren’s rankings. This is because his rankings were mainly based on ‘obedience trials’, this gave an edge to working dogs such as Border Collies who love to work and obey commands.

Therefore, chihuahuas are labeled ‘below average’ in terms of intelligence compared with other dogs according to Stanley’s research. However, dog owners opine that chihuahuas make up for this lack of obedience intelligence with high adaptivity and their sharp wit.

The toy breed is extremely keen on its surroundings and environment. This perceptiveness combined with their alertness and agility ranks them in one of the top ten watchdogs according to pet experts.

As they love having company and being around humans, they make great family-friendly pets, even for small apartments. It is, however, recommended that any children in the family be gentle when approaching and playing with these small dogs.

Do Chihuahuas have a good memory? Are they fast learners?

Although dogs use two forms of memory, their short-term memory is considered a good indicator of their fluid intelligence. The higher the capacity of storing items in their short-term memory, the greater their IQ.

A chihuahua’s short-term memory, according to research, is very limited compared to humans. If you give them a treat as positive reinforcement, they will forget within 70 seconds. Similarly, punishing them 2 or 3 hours later for an act will only leave them confused and afraid.

However, with constant and firm positive training methods, chihuahuas are easy to teach new commands. They are usually eager to please their owners and are quick learners.

As long as you provide plenty of treats and make the training experience enjoyable, chihuahuas are happy to abide and learn commands.

Final Thoughts

In conclusion, the brain of a chihuahua is roughly the size of a tangerine or orange. Although this is the standard size for all breeds of dogs, chihuahuas are still considered to possess the biggest brain in the canine kingdom relative to their body size. Their brain is approximately 55.10 grams.