How Do You Tell If A Frenchie Is A Boy Or Girl?

Telling whether a French Bulldog (Frenchie) is male or female is actually quite simple once you know what to look for. There are a few clear physical and behavioral differences that can help you identify the sex of a Frenchie puppy or adult.

1. Check the Underside (Physical Differences)

• Male Frenchie – Has a small bulge (scrotum) located between the hind legs, and a visible penis situated on the lower belly, just in front of the hind legs.
• Female Frenchie – Has a vulva, which appears as a small opening located just below the tail, between the rear legs, and there is no bulge underneath.

If you’re looking at young puppies, the males’ testicles may not have fully descended yet (this usually happens around 6–8 weeks of age).

2. Size & Build Differences

• Males are typically heavier and more muscular, with a larger head and broader shoulders.
• Females are usually smaller, lighter, and more compact, with a slightly narrower frame.

These size differences become more noticeable as the dog matures.

3. Temperament & Behavior Clues

While every dog’s personality is unique, some general trends can help:

• Males tend to be more playful, outgoing, and sometimes more territorial.
• Females can be calmer, more independent, and often easier to train in some cases.

Behavioral traits vary widely, especially after spaying or neutering, so physical examination is always the best way to confirm.

If you’re unsure and want to confirm safely, ask your veterinarian to check during a routine visit. They can easily determine the sex in seconds, even with very young puppies.

Look underneath the puppy, boys have visible genitals on the belly, girls do not. Once you know what to look for, it’s easy to tell them apart.