Introduction

Dogs are amazing animals. They’re loyal, they’re affectionate, and—of course—they have a much better sense of smell than we do. As anyone who has ever owned a dog knows, their noses are fantastic. Dogs can smell things that we can’t even imagine: A scent on the wind? No problem! A faint whiff of perfume left behind by your neighbor’s cat? Not an issue! A whiff of human sweat from someone who walked past this spot earlier today? Easy peasy lemon squeezy! Dogs’ sense of smell is so good that some researchers believe it’s actually better than ours (and I’m not just talking about dogs in general). You see, humans have about 5 million olfactory receptors in their noses while dogs have 100 million—which means that dogs can detect odors at concentrations way lower than we do (which is why they’ll sometimes start sniffing something when you just think it smells like nothing).

How much better is a dog’s nose than a human’s?

While the exact number of olfactory receptors varies by breed, dog’s can have anywhere from 125 to 300 million scent receptors. Compare that with the 5 million we humans have, and it’s easy to see why they can detect odors at concentrations 1,000 times lower than humans can. Their noses also work on a different level than ours: instead of being able to recognize just one scent at a time, dogs are able to pick up multiple smells at once—both those coming from their environment and those emanating from one another. This allows them to identify scents even when they’re miles away.

Why do dogs have such good noses?

Dogs have a super sense of smell. They can detect odors in the air at concentrations that are 1 part in 10 billion. Humans, on the other hand, only smell odors at concentrations of 1 part in 100 million. This is because dogs have about 220 million olfactory receptors while we humans have just 5 million! The more olfactory receptors you have, the better your sense of smell will be (and vice versa).

What can dogs smell?

Your dog’s nose is much more sensitive than yours. It can smell a drop of blood in a swimming pool and detect the tiniest scent on the breeze. In fact, dogs have between 125 million to 200 million sensory cells in their noses, whereas humans have only 5 million to 7 million sensory cells in theirs. This means that your dog has an estimated 40 times more scent receptors than you do!

A dog’s sense of smell is so acute that it can detect even less than 1 part per trillion (the same as one drop in 20 Olympic swimming pools) and can sniff out odors up to four miles away—or nearly six times farther than us humans!

Can humans smell anything like as well as dogs do?

Sure, you can smell the pizza in the oven and that guy sweating on the bus. But can humans smell anything like as well as dogs do?

Dogs have a much more sensitive sense of smell than humans do. Their olfactory bulbs are bigger and contain more receptor cells—the nerve cells that detect smells—than ours. Dogs also have twice as many genes for making odorants (that is, chemicals involved in scent detection) than we do. Plus, humans have about 10 times less mucus in their noses than dogs do; mucus helps trap airborne molecules for our noses to analyze and identify them later.

How do dogs use their sense of smell to communicate?

Canines use their sense of smell to communicate with other dogs, humans and the environment. Your dog may leave his scent on your shoes so that you can find him if he runs away from home. He may also mark territory in order to tell other dogs that this is his land.

How does a dog’s sense of smell come in handy for humans?

Dogs can be trained to sniff out anything from drugs, explosives and other illegal substances to cancer cells. They can also be used to detect medical conditions such as diabetes, liver failure and heart disease. Dogs are also trained to sniff out bed bugs, termites and other pests that threaten our homes or food supply.

What does it mean when your dog is sniffing the ground or something else intently?

When your dog is sniffing the ground (or something else), he’s likely trying to get a better sense of his surroundings. He may be attempting to get his bearing, or figure out where he is in relation to other things around him.

This can be especially important if your dog has been lost and hasn’t had any recent contact with other humans (or even other dogs). If that’s the case, he’ll probably need some help learning what the world looks like from here on out.

If your dog seems nervous about something, take this opportunity to explore with him and see what there is for him to learn about this new environment.

What if my dog can’t smell things very well?

If your dog can’t smell things very well, it could be a sign of something serious. There are several reasons that a dog’s sense of smell may be compromised:

• Infection
• Sinus infection
• Allergies or asthma
• Cancer in the nose or sinuses (nasal carcinoma)

Dogs are awesome.

Dogs are amazing. They’re loyal, loving, and fun to be around. They make us happy and give us unconditional love. They’re cute too!

Conclusion

Dogs have a remarkable sense of smell and it’s not just for smelling bad things. They can use their nose to tell us about their environment, find lost people or animals, and even detect cancer in humans. If you want to get your dog started on training in scent work or search & rescue activities, then we recommend reading our blog post about canine nosework!