Gender

**Gender** is a characteristic of Pokémon and humans in the Pokémon world.

Most Pokémon have a gender: male or female; however, some species of Pokémon are gender unknown. The gender mechanic is fundamental to Pokémon breeding.

The player can choose between a male or female player character. However, human men and women have appeared in all core series Pokémon games.

## Pokémon

### Determining gender

One factor that determines gender is each Pokémon species's gender ratio, which is approximately how likely a Pokémon is a specific gender instead of the other.

`00000000 00000000 00000000 00000000`

A Pokémon's gender is determined by the personality value's lowest eight digits (the lowest byte, highlighted in red above) of *p* in binary form. Mathematically, this can be derived by calculating `*p* % 256`. Below, this value will be referred to as *pgender*.

In a Pokémon species' data structure, there is a value called the *gender threshold*, a byte with a value ranging from 0 to 255. With the exception of a few special cases, *pgender* is compared to the gender threshold to determine if the Pokémon is male or female.

If the gender threshold is not a special value (0, 253, 254 or 255), *pgender* is compared to the gender threshold. If *pgender* is greater than or equal to the gender threshold, the Pokémon is male, otherwise it is female. This causes Pokémon with a "1:1" gender ratio to be distributed according to the ideal ratio, but all other Pokémon are more likely to be the more common gender than they would be according to their nominal ratio.

If a species has a gender threshold of 255, all Pokémon of that species are gender unknown (such as Magnemite). If a species has a gender threshold of 254, it is a female-only species (such as Nidoran♀). If a species has a gender threshold of 0, it is a male-only species (such as Nidoran♂).

If a Pokémon with Cute Charm is in the first place in the party (even if fainted), there is a 66.7% chance that the game will force an encountered Pokémon to be the opposite gender to the Pokémon with Cute Charm if it can be that gender.

### Gender differences

*Main article: List of Pokémon with gender differences*

Some Pokémon feature minimal differences in sprite between two specimen of the same species. For example, a male Raichu will have the full tail, while the female is missing the very tip of it. Other Pokémon habe more drastic differences in appearance.

The only Pokémon with gender differences that are not just aesthetic is Meowstic, who has different learnsets and sets of Abilities depending on its gender.

#### Meowstic

The male Meowstic has Prankster and the female Meowstic has Competitive as its Hidden Ability. At certain levels, they learn different moves from one another: the male Meowstic learns status moves, while the female Meowstic learns special moves. Female Meowstic learns one gender-exclusive status move, Me First.

### Single-gender Pokémon

#### Nidoran lines

The Nidoran family is a special case in terms of gender. Nidoran♀ and Nidoran♂ are considered separate species of Pokémon and indeed have many differences, from appearance to moveset. However, Nidoran Eggs have a 50/50 chance of hatching into either Nidoran♀ or Nidoran♂.

#### Firefly Pokémon

In a manner similar to Nidoran, Eggs produced by Illumise may hatch into Volbeat.

#### Eon Pokémon

While Latias and Latios are in the No Eggs Discovered Group, likely due to being Legendary Pokémon, they are similarly related.

#### Gender-based evolutions

Some Pokémon may have different ways of evolving depending on their gender. These Pokémon may therefore have one or more evolutions that can only be a single gender.

Eviolite will always work on Combee and Salandit, regardless of their gender and whether they are able to evolve.

#### Other single-gender Pokémon

The following is a list of all Pokémon that are either 100% male or 100% female and have not been mentioned in an above section. In particular, these Pokémon have no explicit relation to a Pokémon of the opposite gender through evolution or breeding, although some of them may have a counterpart.

#### Single-gender forms

Certain forms of Pokémon are exclusively one gender. None of the Pokémon with these forms can breed.

### In battle

The Love Ball is more effective when catching Pokémon that are of the opposite gender of the player's Pokémon.

The following moves are dependent on gender:

The following Abilities are dependent on gender:

## Humans

*Main page: Category:Characters by gender*

Players are given the option of choosing to play as a boy or girl Trainer at the start of the game.

Some Trainer classes have male and female variants, such as Swimmers, while others appear to be counterparts, such as Campers and Picnickers. Others, such as Kimono Girls, have no opposite-gender counterpart.

Availability of different clothing is gender-specific for the male player.

Outside of battle facilities, the gender of a non-playable character often determines the default gender of their Pokémon. If the Pokémon's species has an even 1:1 gender ratio, then its gender will match its Trainer's; if the gender ratio is skewed, then the more common gender of the species will be used.

For some Trainers, especially Gym Leaders and the Elite Four, the default genders have been overridden to give their teams a more balanced gender distribution.

## Trivia

* Although its name suggests that it is exclusively male, Mr. Mime may be of either gender.
* Although they are gender unknown Pokémon, Solgaleo and Lunala are said to be the male and female final forms of Cosmog, respectively.