Look at the Genitalia
One of the easiest ways to determine the gender of your cat is to look at their genitalia. Females have a slit-like opening, while males have a round opening. The female cat’s genitalia, called the vulva, is located below the anus. The male cat’s genitalia includes the scrotum and penis, located just below the anus. The most obvious difference is that female cats have an external slit-like opening, while male cats have a round opening.
Observe Behavior
There are some notable behavioral differences between male and female cats. Females tend to be more affectionate and attached to their human companions. They are more likely to rub against legs, jump on laps, and sleep in bed with their owners. Males, on the other hand, are more aloof and independent. They bond more with territory than with specific people. Male cats also tend to be more aggressive and territorial, especially if they have not been neutered. They are more prone to urine marking around the house and aggression towards other cats. In multi-cat households, female cats generally co-exist more peacefully and develop positive relationships with each other. Male cats can be more difficult to integrate and often compete for territory and status.
According to this article, male cats tend to be more social and affectionate with other cats in the home, while female cats reserve most of their affection for their human companions.
Examine Physical Features
One of the most noticeable differences between male and female cats are their physical features. Males are generally much larger than females, with some breeds having males that are 25% larger than females. Males have broader heads, necks, and shoulders, as well as more muscle mass.
Females have smaller, more delicate heads in proportion to their bodies. Their shoulders and hips are also more narrow. These physical differences are due to hormones, as testosterone causes more muscular growth in males. The size difference can be apparent even in kittens. So just by observing your cat’s overall size and bone structure, you may be able to distinguish males from females.
Check for Mammary Glands
One way to differentiate between male and female cats is to check for mammary glands. Female cats have mammary glands that are visible as rows of nipples along their belly, while male cats do not develop mammary glands.
According to the OSU Veterinary Medical Center, mammary tumors are occasionally seen in male cats but the vast majority develop in intact females. The presence of mammary glands and nipples is a clear sign that a cat is female [1].
Feline mammary hyperplasia, an enlargement of the mammary glands, is also primarily seen in female cats according to UC Davis, providing further evidence that visible mammary glands indicate a female cat [2].
The Merck Veterinary Manual states that mammary hypertrophy, another mammary gland condition, occurs mainly in female cats [3]. The presence of mammary glands and nipples can therefore reliably distinguish female cats from males.
Look for Spraying Behavior
Spraying urine to mark territory is more common in male cats than female cats, especially if the male cat is not neutered. Intact male cats are the most likely to spray urine in order to mark their territory. Though female cats and neutered males can spray as well, it is much less common.
According to WebMD, “Unneutered male cats are the most likely to mark.” The urge to mark territory is linked to testosterone levels, which are higher in unneutered males. Neutering typically reduces or eliminates spraying in 90% of male cats.
While female cats are less likely to spray, Gray Group International notes that “10-15% of cats who spray are female.” Intact females may spray while in heat, and neutered females may spray due to stress, anxiety, or medical issues.
Overall, while any cat can spray urine, male cats do so more frequently as a territorial behavior. An unneutered male is the most likely candidate for urine spraying indoors.
Get a Vet Exam
A veterinarian can definitively determine the gender of a kitten through a physical examination. Vets are trained professionals who know what to look for when identifying a cat’s sex. Some key things a vet checks during an exam to determine gender include:
- The presence or absence of testicles in males
- The shape and appearance of the genital opening and surrounding area
- Whether a female cat has an intact hymen
Veterinarians have experience examining many cats, so they can quickly identify anatomical and physiological differences between male and female cats. Taking a kitten to the vet for an examination is the most certain way for owners to learn their pet’s gender. According to the American Veterinary Medical Association (AVMA) [1], “Determining the gender of kittens can be difficult and may require a veterinarian’s professional skills to sex young cats.”
Some visual signs of gender may be ambiguous in very young kittens, so an experienced vet is needed to be 100% sure. A kitten’s reproductive organs develop more clearly over time, but owners don’t have to wait if they want to know the gender right away. Simply scheduling a veterinary exam is the best way to get an accurate answer.
Consider Coat Colors
The coat color and pattern of cats can provide clues about their sex. This is because the gene for coat color is carried on the X chromosome. Female cats have two X chromosomes, so they can display a greater variety of coat colors and patterns. Male cats have only one X chromosome paired with a Y chromosome, which limits their coat color options.
For example, orange tabby cats are about 80% likely to be male according to the Animal Hearted blog. This is because the gene for orange coat color is only found on the X chromosome. Since male cats only have one X, if they inherit the orange gene they will display that coat color. Females need to inherit the orange gene on both X chromosomes to display an orange coat, which is rarer.
On the other hand, a calico or tortoiseshell coat pattern is almost always found in female cats. This is because the calico pattern requires two different coat color genes, which requires two X chromosomes. If a male cat inherits the calico genes he is usually born with genetic abnormalities and is sterile.
So while coat color alone can’t definitively determine a cat’s sex, orange coats point to males and calico/tortoiseshell coats indicate females in most cases.
Notice Voice Pitch
Female cats tend to have higher-pitched meows compared to males. This is because males usually have larger vocal cords and vocal tracts, which leads to deeper meowing sounds.
According to a Quora discussion, the pitch difference is noticeable enough that many cat owners can tell if a strange cat is male or female just by hearing it meow from another room. The higher pitched female meows can sound loud and demanding to humans. Source
Some Reddit users joke that the gender stereotype of women having higher pitched voices extends to female cats as well. However, it’s simply an anatomical difference that affects pitch, not a difference in personality or behavior between genders. Source
Check for Heat Cycles
Female cats go into heat cycles, called estrus, when they are able to reproduce, usually around 6-9 months old. Estrus cycles occur every 2-3 weeks and last about 7 days on average if the female cat is not spayed (source). Some signs that a female cat is in heat include loud vocalizing day and night, rolling around, treading with the hind legs, and holding the tail to the side when scratched near the base of the tail (source). These signs indicate the cat is in her fertile period and is receptive to mating with male cats. If the female cat does not become pregnant during a heat cycle, she will go into heat again usually within 2-3 weeks. Getting the cat spayed will stop the heat cycles from occurring.
Look for Testicles
One of the most definitive ways to identify the sex of a cat is to check for the presence of testicles. Male cats normally develop testicles by 4-6 months of age.1 The testicles descend into the scrotum as the cat matures. In some cases, one or both testicles may fail to descend properly into the scrotum, which is called cryptorchidism or an undescended testicle.2, 3 If you don’t see testicles descended in the scrotum of a 6+ month old cat, it may be a female or a cryptorchid male. Consult a vet for confirmation.
