It's the end of the day when your dog lets out a long, loud sigh before plopping down on the couch and falling asleep. You may ask yourself: why is my dog sighing like she had such a rough day when she really just slept and played the entire day? Chances are, your pup isn't actually sighing out of annoyance like humans might, but rather expressing more positive emotions. 

Sighing is a common noise many pups make on the regular—but what is it our furry friends are trying to tell us with these drawn-out breaths? Is it ever a cause for concern? 

Sighing is basically a long, sharp exhale common in dogs as well as other species like humans. Dogs can sigh at any time—but many times it happens right before they go to sleep or lie down. 

You can tell if your dog is sighing when you hear them release a deep exhalation. Sighing is different from other common dog noises, such as barking or whining, as the noise is simply made by breathing and not vocalization. 

Sighing can indicate positive or negative emotions in dogs—and an easy way to tell what your dog is feeling is by observing their eyes. The American Kennel Club says that when a "sigh is combined with half-closed eyes, it communicates pleasure; with fully open eyes, it communicates disappointment." 

Sighing is another way our dogs communicate with us—similar to how they communicate through vocalization and body language. The nature of the sigh as well as your pup's expression and body language can tell you how your canine pal might be feeling. 

Contentment is one of the biggest reasons dogs sigh—especially if they sigh while resting or before lying down. If your dog lets out a loud sigh after a fun day and proceeds to settle in and relax, there's a good chance they let out that breath because they feel content and safe. 

Rhiannon Koehler, DVM, MPH, says that if "your dog's laying down, just kinda resting and you hear them sigh, that's usually going to be just that nice sign of contentment that they're comfortable in their environment." 

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Dogs may also sigh out of exasperation or frustration. Koehler says it's more likely your pooch is sighing out of contentment, but there might be times when your pup lets out an exasperated sigh. 

Your dog might let out an exasperated sigh when they want to do something, such as play or walk, but you aren't giving them what they want. Keep an eye on your dog's facial expression when they sigh, and if your pup has the open-eyed look described by the AKC, they could be feeling frustrated. 

Similar to contentment, dogs also sigh when they're feeling relaxed. If your dog sighs before sleeping or laying down—they are likely just expressing their comfort. 

While Koehler says true sighing typically isn't anything to be concerned about—if your dog is having a lot of heavier breathing, gasping, or making other noises such as groaning, you should talk to your vet as these could indicate an underlying medical condition. 

"[Sighing] doesn't typically point to any medical issues that are underlying it," Koehler says. "If it's not sighing and it's more of a groaning or a gasping breath then that's when you would want to be concerned. That could indicate something like a heart issue." 

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