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How to Tell if a Hamster is a Male or Female

Holding Your Hamster to Determine Its Sex


Whether you’re picking a name for your furry friend or you’ve decided to raise two hamsters together (remember, hamsters are solitary animals, so they most will prefer that you are their only friend), it is important to know whether your hamster is a male or female.  Female hamsters enter a heat cycle approximately every four days and their gestation lasts anywhere from 16 – 22 days depending on the species, so making sure you do not accidentally allow male and female hamsters to cohabitate is critical.

So… what should you look for?  Typically, the larger and more mature your hamster is, the easier it is to determine its gender.  You’ll want to look at space between their genitalia (vaginal and penile openings) and their anus.  In females, the space between the vaginal opening and anus can sometimes be so close together that it looks like a single organ. In males, the space will be farther apart than in females and the testicles may be visible. Remember though, testicles are not always visible in juveniles and even adults can sometimes retract their testicles, so it is important to focus on the anogenital spacing. 

Syrian FemaleSyrian Male

Dwarf FemaleDwarf Male


Another differentiator is their nipples or lack thereof.  Female hamsters have six pairs of nipples whereas males do not have any.  Males also tend to have larger scent glands than females.  These are located on the flanks of Syrian species and on the stomachs of dwarf species.

Holding Your Hamster to Determine Its Sex

Ready to take a look?  Let’s start by making sure your hamster is awake and calm.  Speak softly to them and pick your hamster up by gently grasping it from behind with your hand cupped over its back.  Holding your hamster up in an upright position versus turning it on its back may make your hamster more comfortable and not cause it to squirm as much.  Additionally, holding a male hamster in this position may help his testicles distend, making them more visible.  Always be careful and monitor your pet’s demeanor to help prevent bites if your hamster is not used to being handled. Offering a treat can sometimes distract a hamster while you determine whether your new buddy is a male or female.

Reviewed by Petco’s Animal Care, Education and Compliance (ACE) Team

Petco’s ACE team is a passionate group of experienced pet care experts dedicated to supporting the overall health & wellness of pets. The ACE team works to develop animal care operations and standards across the organization and promote proper animal care and education for Pet Care Center partners and pet parents, while also ensuring regulatory compliance.