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Why Do Big Dogs Think They Are Small?

Big dogs can do funny things, such as trying to sit on your lap, even though they are definitely not lap dogs.


This experience is common for many dog owners, so why do big dogs think they are small?

Big dogs may think they are smaller than they are because they aren’t always aware of their size or don’t realize they are no longer a puppy. 

In this article, I will discuss if dogs understand their size and why big dogs may think they’re smaller than they are. 

Can Big Dogs Tell That They’re Big?

It is not certain if big dogs know that they’re big. 

Some studies suggest that they do, while the actions of a lot of dogs indicate that they don’t truly know their size. 

Other research shows that dogs know the size of other dogs around them but may not always understand their size. 

Experts have shown that dogs may know the size of other dogs by their bark or growl.

According to Science.Org, dog ears perceive the size of a dog through the loudness of the bark/growl and the pitch.

That said, it is not clear if all big dogs know they are big themselves.

This observation comes from many owners sharing information on forums, conversations, and from pictures of big dogs trying to act small.

Examples of Big Dogs Acting Small

One example is a large dog trying to lay on someone’s lap, which may be very awkward due to its size.

Another instance is large dogs trying to sleep in small animal beds that their bodies can’t even fit halfway into. 

Why Big Dogs Act Small

These behaviors suggest they no longer know they’re too big for these particular places. 

This misconception could be because they knew they could do those things as a puppy and don’t understand they’re not puppy-sized anymore. 

A similar instance to this involves horses.

When horses are foals, the fence surrounding them is taller than they are, so they know they can’t jump over it.

When the horse is fully grown, it can easily jump over the fence if they want to, but they don’t because they think it is too big for them to hurdle. 

The horse learned this relationship at a young age because they couldn’t, and they still have the same mindset. 

Many Big Dogs Seem to Have an Idea of Their Size

Many big dogs know their size, at least somewhat.

Owners have reported their large dogs being very gentle with small children or smaller animals, suggesting that the dog knows they’re bigger and could accidentally harm something smaller.

Another suggestion is that large dogs know they’re too big to sit on your lap but don’t care.

Your dog just wants to cuddle with you, and their size doesn’t stop them from trying to make it work. 

When you consider all of this, dogs may know their size when it comes to interactions with other animals or children, but when it comes to laying in a bed, fitting through a door, and trying to be a lap dog, they don’t want to do it.

Do Big Dogs Know the Size of Other Dogs?

It is unknown whether big dogs know that other dogs are smaller or larger than them. 

Some dog owners suggest they do, but it’s tough to prove.

The apparent suggestion is that big dogs can see that another canine is considerably smaller through eyesight and hearing.

However, that doesn’t mean they know for sure they are considerably larger than the other dog. 

As suggested earlier, research shows that dogs know the size of other dogs through their bark and growl.

Small dogs probably use the same tactics to figure out how big other dogs are, but this still doesn’t answer whether small dogs know if they’re small or not.

Many small dogs exhibit behaviors of not being bothered or scared of large dogs, while others will be noticeably anxious. 

According to Petite Pup Daycare, this could be because some dogs are fearless and aren’t bothered by another dog’s size, while others may be more fearful and anxious

Small dogs may try to play with larger dogs without realizing they’re at a disadvantage. 

Behaviors like this suggest that dogs may know the difference in size but don’t realize the advantages or disadvantages of their own stature in comparison. 

Letting Big Dogs Play With Small Dogs

We may never know what goes through a dog’s mind regarding its size and other dogs’ sizes. 

However, when it comes to playing, owners should still practice precautions when allowing dogs of different sizes to play together. 

Many small dogs are anxious when playing with larger dogs, so if your small dog exhibits this behavior, it may be best not to put them in that situation.

If you have a large dog that sometimes doesn’t know its size, it may be best to let it play with other large dogs. 

A dog could end up getting hurt accidentally if rough play fighting ensues. So, it’s best to be cautious to avoid something like this from happening. 

However, if the dogs involved have no issues and are playing nicely with each other, it is acceptable to let them continue.

You should keep a close eye on them because the larger dog could accidentally step or trample on the small one if they aren’t aware of their size. 

Always be cautious when it comes to dogs you aren’t familiar with, and keep an eye on your own dog’s mannerisms and behavior around these dogs.

Check out my article detailing whether you should let puppies play with big dogs for more information. [Should You Let Your Puppy Play With Big Dogs?]

Final Thoughts

Big dogs may think they’re small because they don’t realize they’re no longer puppy-sized. 

Studies suggest dogs know the size of other dogs from the loudness and pitch of their bark, but this doesn’t prove they know how big they are themselves.

Many dog owners say their large dog plays gently with small children or small pets as if they know they’re bigger. 

With all this information, we can only assume that dogs know other dogs’ sizes and when to be careful but don’t always realize their own size.