Though salamanders should not be handled by humans, they can still make fascinating pets. In order to breed salamanders or understand some of their behaviors, it's important to know their sex. Though it can be difficult to conclusively determine the sex of a salamander, careful observation can yield a fairly accurate answer.
Compare the tail lengths of your salamanders. Males have longer and thicker tails than females do. If you have only one salamander, you'll need to see other salamanders for comparison. Try comparing your salamander's tail to the tails of salamanders at a local pet store.
Look closely at the tail. Salamanders have a ridge on the top of their tails called a tail fin. This fin makes swimming easier and is larger in males than in females. The tail fins of females will be almost invisible, while the tail fins of males will be immediately noticeable.
Watch for seasonal color changes. Both male and female salamanders undergo moderate changes in coloration during breeding season. Males tend to become very brightly colored during breeding season. The color change in females is not easily noticed. If you've observed your salamander changing colors occasionally, it is likely a male.
Observe the cloacal region. This is where the salamander's genitals are located and can be found on the underside of the salamander where the tail meets the body. During the breeding season, the cloacas of male salamanders become swollen. This swelling is the most conclusive way to sex a salamander. If the cloacal region swells, it's a male.