How To Sex An Axolotl? [Male or Female]

Unsurprisingly, one of the questions that I get asked a lot is: “Is my axolotl a boy or a girl?”. Indeed, axolotls are notoriously hard to sex. It can be very difficult to clearly identify what gender they are.

With animals such as dogs, for example, it’s fairly simple…let’s say that male dogs have extra “gear” between their rear legs that bitches don’t have. However, the physical differences between male axolotls and female axolotls are very subtle – especially for the untrained eye…

But despair not!

As you’ll read in the following axolotl sexing guide, it’s possible to sex your axolotl when you know what to look out for, and when to look out for it! So, if you’re an axolotl owner trying to figure out whether you own a male or female axolotl, or how to sex axolotls, you’re in the right place.

Table of Contents

How To Sex An Axolotl Featured Image

When Is It Possible to Tell an Axolotl’s Sex?

When you get a pet, one of the first things you think about and do is decide upon a name. The main issue here is that it can actually be very hard to tell the sex or gender of an axolotl, especially when they are juveniles. This makes choosing a name a challenge unless you go for something that is gender-neutral. 

So, how to tell if an axolotl is a boy or girl?

The process of sexing an axolotl becomes easier as the axolotl gets older and reaches sexual maturity. In other words, sexing axolotls is only possible at a later stage in an axolotls life cycle.

Sexual Maturity

To determine the sex of your axolotl, you will most likely have to wait until it has reached sexual maturity. Before that stage, you’ll probably just end up guessing! 

Sexual maturity is the capability of an organism to reproduce. We tend to consider that an animal reaches adulthood when it becomes sexually mature.


Typically speaking, axolotls reach sexual maturity anywhere between the ages of 6 to 12 months. Occasionally become sexually mature as early as 5 months old and others as late as several years old. The speed at which your axolotl will become sexually mature will of course depend on genetics but will also be influenced by factors such as water or feed quality.


At that stage in their lifecycle, axolotls generally reach around 8 inches or 20 cm in size.


When axolotls reach sexual maturity, their toes will start changing color. This is generally a good indicator that your axolotl is reaching adulthood. The toes of lighter-colored axolotls will begin to darken and the toes of darker-colored axolotls will begin to lighten.

Can You Sex A Baby Axolotl?

It is notoriously difficult to sex an axolotl, and it is even harder to try and do it before they reach sexual maturity.

So no, for the most part, you cannot sex a baby axolotl. You will most likely have to wait until they are at least 6 to 8 months of age before attempting to identify the gender. 

So, now that you know that it’s more or less pointless to try to sex a juvenile axolotl and that you need to wait until your axolotl is sexually mature to determine its gender, let’s now explore the different things you can look out for to understand whether your axie is a male or a female.

How to Tell an Axolotl’s Sex (Male vs Female Axolotl)

Watch Your Axolotls Breed

One of the more distinctive ways that you can tell whether an axolotl is male or female (i.e. determine axolotl gender) is by watching the breeding process. Males and females behave differently during mating, so you will be able to define their gender by watching them mate. 

When axolotls breed, male axolotls tend to wiggle their tails and will go around the tank laying sperm cones everywhere. These are known as spermatophores.

On the contrary, females tend to follow them around, with their noses against the cloaca.

Then, the males will attempt to push the female to get her to land on the sperm cone, so that it can be absorbed into her body. Once absorbed, the female will start to deposit eggs and lay them around the tank for an extended period of time. 

You can watch this process to see how the axolotls behave in order to see who is the male and who is the female. If you see an axolotl being more aggressive during the mating process, then they are probably male. If you see an axolotl laying eggs, then it is almost certainly a female. 

However, this method for how to tell axolotl gender will only work if you have male and female axolotls in the same tank, and if it’s mating season. Therefore, it’s hard to rely on this method alone to sex your axie.

Check Your Axolotl’s Cloaca

Another simple way to tell whether your axolotl is male or female is to take a look at the area on the body called the cloaca. The cloaca is the little part behind their back legs, just before the tail end of the axolotl. 

With a female axolotl, the cloaca is typically flat against the body, with no bulge near the tail. However, females can get a poop bump’ on the cloaca, which can make it look slightly swollen, or the area can sag down to a V or U shape. However, it is still not a bulge. The cloaca is also noticeably shorter in females than in males.

After defecating (a fancy way of saying going to the bathroom), the poop bump should go away. The cloaca will then become flat again and back to normal. 

In comparison, after an axolotl has reached sexual maturity males will get a bulge in the cloaca area.

The male axolotl will have a noticeable bulge just behind the back legs before the tail. Whilst some bulges may be larger and more defined than others, all males will have one. 

In addition to this, male axolotls tend to have longer cloaca areas than females, and the bulge will become increasingly prominent and defined during the breeding process. 

Look At Your Axolotl’s Body Shape

Male axolotls tend to be leander than female axolotls
Axolotl Male vs Female

There are other ways to determine the sex of your axolotl, such as examining the body shape.

Like many other creatures, the body shape of an axolotl is different in males and females. So, you can take a look at their silhouette to try and identify the sex. It’s also worth noting that in this case the best angle to observe your axolotl is from above.

For instance, a female axolotl tends to have a much rounder body shape than a male axolotl. This is because pregnant females are capable of carrying eggs and their body has evolved to support this. Therefore, they tend to be a little bit wider in the stomach area, and further along the body. 

Some female axolotls may even look slightly pear-shaped, especially when they are carrying eggs after the mating process. Sometimes, if no males mate with the female axolotl, then she will reabsorb the eggs, which can also make them look rounder. 

This is why female axolotls tend to be more rounded than males most of the time, regardless of what stage in their life. In comparison, male axolotls tend to look much more slender and thinner than females.

This also helps to identify the cloaca, as the bulge mentioned above is so much more pronounced in contrast with the rest of the body.

Compare The Sizes Of Your Axolotls

Another method you can use is to check the size of your axolotls.

Generally speaking, female axolotls are bigger than males and tend to be longer. However, this is not the case 100% of the time, so it is not always a reliable method of sexing the axolotl but can be used in conjunction with the techniques highlighted above.

Some males can also get rather large due to their genetic makeup, or the diet they are on. That being said, you could have two axolotls of the same size roughly in length, one male, one female, and the female will still look much more rounded, whilst the male can look skinnier and scrawnier in comparison. 

Can Axolotls Change Sex?

Axolotls cannot change sex. They are born as either a male or a female, depending on the chromosomes they inherit from their mother and father. They will retain that sex/gender for the entirety of their lives.


To conclude, axolotls are very mysterious, strange, and elusive creatures. They have a unique genetic makeup that makes them very hard to sex.

However, it is not impossible to sex an axolotl, you just have to know at what stage in their lifecycle their gender becomes identifiable and which markers and signs to watch out for.

With this guide, you will know what age you can sex an axolotl, where on the body to look for signs of their gender, and how the males and females differ in size and behavior.

And last but not least, you won’t have to hold off giving your axolotl a name any longer!


Hello and welcome to Pets From Afar. I'm Glen. My daughter Siri and I are mad about axolotls. I created this website to document our findings and experiences, as we learn more about these amazing amphibians. Follow along and enjoy the fun!

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