Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

How to Tell if a Puppy Is a Boy or a Girl: Vet-Approved Way

Share

veterinarian examining a labrador retriever puppy

While you can’t always tell the difference between male and female adult dogs from a distance, there are physical and behavioral clues that can help. When it comes to puppies, however, especially newborns, it can be a lot harder to tell if a puppy is a boy or a girl.

If you’re dealing with a litter of newborn puppies or just aren’t sure how to determine the sex of your new baby dog, we’re here to help. In this article, we’ll teach you how to tell if your puppy is a boy or a girl and discuss the differences between the two.

divider dog faces oct 2024

Before You Begin

Be cautious about removing newborn puppies from their mother. Some mother dogs are very protective and it’s important to give them time and space to bond with their puppies. While you should keep handling to a minimum for the first few weeks of their lives, you will need to touch the puppies occasionally.

For example, you’ll want to monitor their weight to make sure they’re growing properly and to see if they are boys or girls. Consider having someone else take the mama dog for a short walk in the yard while you check on the puppies if she is especially protective.

Playing puppies
Image Credit: Anita Kot, Getty images

How to Tell if a Puppy Is a Boy or a Girl

1. Don’t Rely on Size

For most breeds, adult male dogs are taller and heavier than females as a breed standard. However, you can’t rely on the size of newborn puppies to tell the boys from the girls.

The birth weight, overall health, and other factors play a role in the puppy’s size. You can’t always assume the bigger babies are the boys.


2. Don’t Rely on Behavior

We’ll discuss some of the behavior differences between male and female adult dogs later in this article. Many of those behaviors are related to hormones and other changes that occur once the dog reaches sexual maturity.

Newborn puppies haven’t undergone these changes yet, so you can’t rely on their behavior to tell you which are boys or girls.


3. Physically Examine the Puppy

To tell if a puppy is a boy or a girl, pick the dog up and look at the belly. At this age, the penis and vulva are similar in size and appearance but are in different locations.

Girl puppies have a visible vulva, often described as leaf-shaped, between their hind legs below the tail. Boy puppies have a penis further up their belly, just below their umbilical area or belly button. These physical features are apparent even in puppies who were just born.

You’re welcome to use our images, but we require you link directly to this site for credit (ex. Image from Dogster)

dogster paw divider

Why Is It Important to Know if a Puppy Is a Boy or a Girl?

If you’re selling or adopting out puppies, you’ll need to be able to tell new owners the sex of the dogs. Most owners prefer male or female dogs based on past experience, the sex of dogs currently in their family, advice from other dog owners, or general assumptions about the behaviors of the two sexes.

According to research, there are differences between male and female dogs, but the data shows some variability. For example, male dogs are more likely to be aggressive and courageous than females. Females show more fearful behaviors on average but are more inclined towards social interactions with humans that require cooperative skills. Males were more inclined towards social play with people.

However, whether your puppy is a boy or a girl isn’t the only factor that controls how they act. Early socialization and training play a vital role in shaping a puppy’s temperament and behavior as they develop.

If you like to talk with a vet to clear out any other doubts you might have regarding this topic, you can consult one online.

If you need to speak with a vet but can't get to one, head over to PangoVet. It's our online service where you can talk to a vet online and get the advice you need for your dog — all at an affordable price!

PangoVet_Mention-in-Content Savings V1

dogster face divider

Conclusion

Determining if a puppy is a boy or a girl at any age is easy once you know what you’re looking for. Deciding whether a boy or girl dog is the best fit for your family might be a bit harder. As we mentioned, it often comes down to the owner’s personal preference. If you don’t plan to breed your boy or girl puppy, talk to your veterinarian about the best time to have them spayed or neutered.


Featured Image Credit: IgorAleks, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything dog

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.




How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.


Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

Can Dog Food Cause Ear Infections? Vet-Verified Facts & FAQ

Dogs, just like humans, can suffer from ear infections. Your dog might never have one, or they may get them routinely. If you...

Gerberian Shepsky Dog Breed: Info, Pictures, Care & More

Picking a dog breed for your family can be overwhelming as there are so many choices to choose from. Big dogs to small...

Interview with Matt Beisner, the Dog Behavior Specialist from Dog: Impossible

Most of us animal lovers are no strangers to the Nat Geo WILD television network as it focuses on all things animal. (Woo...

Happy Tail Syndrome in Dogs: Our Vet Explains the Signs, Treatments & Prevention

Don’t let the name deceive you – Happy Tail Syndrome is not a particularly happy situation. In fact, it can be extremely messy,...

More related

Alpine Dachsbracke Dog Breed: Info, Pictures, Care & Traits

The Alpine Dachsbracke is a rare breed of dog that is thought to have originated in Austria. They look like someone merged a...

Finn’s Dog Food Toppers Review 2026: Micah Tries Pumpkin & Bone Broth Plus

As a dog owner, you want what’s best for your pup–proper exercise, a healthy diet, the best treats on the market. And when...

What Breed of Dog Is Benji? Famous Movie Character Facts

Netflix’s reboot of the timeless classic Benji has landed the loveable homeless mutt into the hearts of a whole new generation. Now, many...

Black Great Dane: Info, Pictures, Origin & History

Black is a standard coat color of the Great Dane. In other words, the black variation is recognized and allowed to compete in...

Keep reading

PetPlate Dog Food & Supplement Subscription Review 2026: Door Delivery For Your Pup Made Fresh

Are you considering switching your dog to a dog food delivery service but struggling to find one that includes enough variety to suit your dog’s needs? If that’s the case, PetPlate might be the best choice for you. This subscription...

DOG_SAPR_PetPlate Human-Grade Dog Food

8 Dog Birthday Cookie Recipes to Treat Your Pup With

This article has been reviewed by a veterinarian for safety. The recipes included in this article will be suitable for most dogs however, it does not take your dog’s circumstances and health status into account. It is your responsibility to...

Dog Birthday Cookie Recipes to Treat Your Pup With

Front of the Pack Dog Food Review 2026: Our Expert’s Opinion

If you’re like most dog owners, you want what’s best for your furry friend. That’s why you’re probably always on the lookout for new and improved dog food brands to try. Well, look no further! In this blog post, we’ll...

Dogster_Front of the Pack Dog Food Review

Can Dogs Eat Brown Rice? Vet-Approved Facts & FAQ

Brown rice is an excellent carbohydrate to include in your dog’s diet. It’s seen as one of the more nutritious types of rice that is safe for your canine companion while being easy to digest. Many households have white or...

Can Dogs Eat_Brown Rice

10 Best Dog Foods for Active Dogs in 2026 – Reviews & Top Picks

If you have an active dog, you may have found that you struggle with keeping weight on your dog, no matter how much you feed them. Some breeds also struggle to maintain their body weight, especially while they’re young. A...

labrador retriever eating dog food

Can Dogs Eat Cream of Mushroom Soup? Vet-Verified Nutrition Facts & Info

If your dog just broke into the trash or snatched a plate of leftovers, you want to make sure that anything they got ahold of is perfectly safe, otherwise, a vet trip may be imminent. The good news is that...

Dogster-Can-Dogs-Eat-Cream of Mushroom Soup

7 Dog Cupcake Recipes You Can Make At Home Today

Dog cupcakes may seem like fancy treats saved for special occasions. However, they can be healthy snacks that you can make for your dog at any time of the year. Homemade dog cupcakes use natural ingredients, and you can control...

Dog Cupcake Recipes You Can Make At Home Today

Can Dogs Eat Turkey Necks? Vet-Verified Nutrition Facts & FAQ

Unless you’re using the turkey neck in a tasty gravy, stock, or soup, many of us can’t think of anywhere else to put them besides the trash. It might seem wasteful, but if giblets aren’t your specialty, what’s the point...

Can Dogs Eat Turkey Necks

Love Dogs? So Do We! Join the Dogster Community

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.




Sign up for the Dogster Email Newsletter