Sexing Gerbils

You have two gerbils. How do you tell if they are both the same sex?

This question arises all the time. It is not difficult to answer as this page will demonstrate. Gerbils are in fact extremely easy to sex from about 5 weeks old upwards. As this earlier than they will normally begin to mate, it shouldn’t be difficult to avoid unwanted pregnancies! With a little experience you should be able to reliably sex gerbils from the third week or sooner.

There are four main differences between male and female gerbils.

  • Adult males are significantly larger, although this is not a precise method of sexing because gerbil size can depend on a number of other factors.
  • Adult males have a large bulge at the base of the tail which is their scrotum. This is totally absent from females. This bulge is obvious by 6 weeks of age and can be seen at least two weeks earlier.
  • Female gerbils have more obvious nipples. I know some people who say they can sex gerbils at a few days old by this method but it isn’t one I would recommend.
  • Finally and most importantly, the distance between the urinary and anal openings in female gerbils is much smaller than it is in males. This method can be used reliably from at least three weeks of age.


So how exactly do I sex them?

  1. The first thing to do is to put your gerbil on your left hand or a stable surface.
  2. Then, gently take your gerbil by the base of the tail with the first finger and thumb of your right hand. (You can of course swap hands if you are left handed.)
  3. Lift the rear of your gerbil of the ground with your right hand. Making sure that it’s front feet can still support its weight on your left hand.
  4. Finally, look at the ventral openings and look for a bulge at the base of the tail. The following photos should help.
7 Weeks old
4 Weeks old

You can test your self using the following picture:


Decide whether you think this gerbil is male or female, then Scroll down to see if you are right.


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If you said the gerbil was male, congratulations! You are right! If you got that wrong, don’t worry, just study the photos some more and you will soon see the differences.