Chipmunks are lively creatures that many find make good pets. Whether you are mating your chipmunks or simply purchasing one, it is important to know the gender of your chipmunk. Knowing the sex of your pet is also important when determining how you will house him, as you shouldn't place a male and female together, unless you are prepared for baby chipmunks. With a little practice and a deciphering eye, it's easy to tell whether your chipmunk is male or female.
Pick your chipmunk up with your hands and place him on his back, with his rear closest to you. Your chipmunk will probably wiggle and protest, therefore, it may take a few times to successfully keep the rodent on its back.
Locate the genitals and anus. These features can be found towards the end of the chipmunk and will appear as two distinct bumps.
Look at the genital area, which is located above the anus. In the genital area, males will have two bumps that are about one centimeter apart from each other. In females, the bumps are touching each other.