Sexing Leopard Geckos

06 July, 2010 13 comments Leave a comment

Knowing what the sex of your leopard gecko is can be extremely important. Without knowing if you have a boy or a girl, how would you even know what to name your gecko, right? Not to mention that if Sasha turns out to be a boy, then he and Zanzibar are going to have a rough go of it—males don’t like other males! Then there is that mental shift you have to make when you believe that Phil is a boy until you realize that he is really Phyllis and you never quite feel the same about him—uh, her. So, we have had plenty of people asking us how to tell if they have a boy or a girl gecko.

One thing that most people find interesting about leopard geckos is that the incubation temperature has a huge impact on the gender of the animal. The lower incubation temps—82 degrees—yield females, while the higher temps—88 degrees—yield males. Middle temps yield a combination of males and females. This is why you see some people referring to geckos as TSMs or TSFs—the TS stands for “temp sexed.” Still there is always the chance you have been duped, so you really need to wait about 3 or 4 months to tell for sure if Mike is really Mike. As the gecko matures, the boy parts start to show. If no boy parts, you have a female—makes sense, right?

If you are not sure what you have, look at the gecko’s under side—also called the ventral side, at the area between the two back legs and just at the base of the tail. A male will form two hemipenal bulges right at the base of the tail, below the vent. A male will also develop a v-shaped row of pores, called pre-anal pores. They use these pores to scent their territory. As a result, you will sometimes see a waxy buildup at these pores. Females don’t have the bulges and the pores are very small in comparison and they do not have the waxy buildup.

This is what you will see:


Congratulations! You are a proud owner of a gecko that is either a boy or a girl, and you can tell the difference!


« Previous post   |   Next Post »


  1. Hollie Mathis April 30, 2016

    I just got a gecko and the guy at the pet store never told me if it was a girl or a boy so I named it Earl and “he” is a girl

  2. Gecko Lover February 14, 2016

    My leopard Gecko is a juvenile and I think it is a female but I’m not completely sure… I can see an egg slit-like thing. SO please help! Boy or girl?

  3. Aokeeton October 21, 2015
    I have a girl!!?
  4. Robby Tiezzi September 29, 2015

    And I named him Flash, I don’t know if its a girl or boy though.

  5. Robby Tiezzi September 29, 2015

    My gecko seems stressed. He trys to like headbutt me every time I try to pick him up, Lol!

  6. Lleyton June 06, 2015

    Mine has preanal pores but not the bulges so I’m confused

  7. Jessi Smith March 05, 2015

    I just got a leopard gecko and named it Lighting. I thought it was a boy. But, I just found out she is a girl! Welcome home Lighting Flower

  8. nancy February 13, 2014

    Thank you, that help a lot..We have a boy!!

  9. Tabitha March 05, 2013

    I just got my gecko 2 weeks ago. It’s extremely young so I still can’t tell it’s sexing this is extremely helpful since I plan on getting another gecko to keep Spirit company.

  10. Amber H January 04, 2013

    The pet store told me our gecko was a boy, but I’m thinking from the pics. above; we have a girl…named Randal :)

  11. scarlett wade June 24, 2011

    i got told my gecko was male but he’s just started laying eggs! but his parts look like a males too.

  12. sherry October 16, 2010

    My Gecko is 4mos. Is this to early to tell if it is a boy or girl? The underneath looks just like the pic of the girl at this time. Thankyou

  13. Cathy Francis August 31, 2010

    Our fam got a fatty from u @ the 2009 expo SLC. Named her Kameike. We LOVE her. Her privates look like something between a boy n a girl. Want to get a new fatty in Oct. Can u tell for sure if ur babies r girls?

Leave a comment

Please note, comments must be approved before they are published

We accept these payment methods:

Amex Discover Google Mastercard Paypal Visa