At some point in your relationship with your dog, you may find yourself wondering whether or not your dog is happy. Happiness is a complicated subject for most humans, not to mention how we might understand it in dogs. Yet there may be times, even frequent times, when your dog is sitting there smiling at you, and you feel like your dog is smiling because it is happy. Most owners learn to tell when their dog either likes or really doesn’t like something, but understanding more nuanced signals like the smile can be confusing. While smiling to express happiness or contentment is one possibility, the truth is that dogs don’t smile the ways human do. Here’s what your dog might really be feeling when it flashes its pearly whites. 

You dog expresses its emotions primarily through body language, not through facial expressions. When your dog wants to express happiness, excitement, or contentment, it tends to do so by wagging its tail, raising its ears, or relaxing its body. The American Society for the Prevention of Cruelty to Animals (ASPCA) says that when it comes to this last expression—contentment—the facial muscles are also relaxed, the mouth is open, and the corners of the mouth might be slightly turned up. This type of smile, with completely relaxed body language, does generally translate to contentment. Some researchers theorize that dogs learned to express contentment with a smile through their intimate domestic history with humans. In other words, they smile because we smile. In fact, humans are an exception to the rest of the animal kingdom in that the vast majority of animals do not show their teeth as a positive or reassuring sign. In most cases, though your dog might appear to be smiling, the expression could be an indication of anything from mild discomfort to severe stress. Reading more subtle cues is necessary in telling the difference between contentment and discomfort, for example—tongue in more commonly means stress, while tongue out more commonly means content. Light panting generally translates to contentment, but heavier panting generally translates to fear. In most dogs, the milder the discomfort, the more difficult it is to tell apart from contentment. When the fear or anxiety becomes strong enough, the smile may appear more starkly as bared teeth, and it may be accompanied by whining or chattering teeth. The ASPCA also attributes smiling to feelings of subordination in dogs, another instance in which smiling does not translate positively. This type of smile occurs when your dog feels threatened or subordinate, and is generally understood to be fearful. Unlike baring teeth in a display of aggression, a subordinate smile is more of a lifting of the upper lip, and is usually accompanied by drooping ears and a hanging head. Though it may be easier to tell the difference between a content smile and a subordinate smile, some dogs have subtler facial expressions that can make it difficult to tell the difference.

If you notice that your dog appears to be smiling a lot, check its other body language to make sure that it is really smiling because it is content. A common scenario in which your dog might look happy, but really be smiling in distress, is when it is being hugged. Though hugging a dog is not uncommon, it is highly likely that it stresses your dog out. It often does not stress dogs out enough that they would whine or show signs of anxiety, especially if your dog trusts you, but by watching carefully as someone hugs a dog, you will notice that the dog tenses up instead of relaxing. 

If you notice your dog smiling at odd times, or frequently, check to see if there is a pattern associated with the smile. If you notice your dog smiling every time you play music, check to see whether or not your dog likes your music, or is stressed out by it. If your dog doesn’t completely relax when you pet it a certain way, consider that perhaps it doesn’t make your dog feel comfortable. If your dog smiles when it sees a certain person, consider whether or not the smile is because your dog is happy to see the person, or nervous. Being able to read your dog is an important part of being able to care for your dog through stressful situations.

Be particularly careful with dogs smiling around children. As a general rule, small children do not make dogs feel comfortable. Quite the opposite, in fact. Even more dangerous, small children do not typically have the ability to determine whether or not a dog is smiling at them, or snarling at them. A study conducted by the University of Lincoln and the Blue Dog Trust showed that 67 percent of 4-year-olds are unable to identify an angry dog’s face, while 30 percent directly mistook angry expressions for happy expressions. Though this number improves as children grow up, it remains a cause for concern until approximately the age of eight or nine. 

Dogs are capable of clear emotional expression, but we tend to project our own emotional expressions onto dogs in order to better understand them. In reality, dogs have their own way of expressing what they are feeling, and like any language, you can learn it with time and practice. So, if your dog is showing its canines, make sure to read the rest of its body language to truly understand what it is trying to say.