The Mii Maker (Mii Channel on the Nintendo Wii) is a pre-installed application on the Nintendo Wii, Nintendo Wii U, Nintendo 3DS, and Nintendo Switch, and is a key feature in Miitopia. The Mii Maker lets the player create Mii characters and add them to the game. It can be accessed while creating Mii characters to fill the roles of NPCs or to create teammates. On the Nintendo Switch version of Miitopia, the Mii Maker is just the normal Nintendo Switch Mii Maker. Up to 100 Mii characters can be kept in one console.
In Miitopia, the Mii Maker is the only way to create a new Mii representing the Hero if the player does not have one yet or does not want to use any available ones they already have or received, as the Mii Central (Nintendo 3DS) or the Mii bank (Nintendo Switch version) is unavailable upon booting up the game for the first time until the Hero Mii is created.
In the Mii Maker, the player can change the following:
- Head shape
- Skin color
- Face details, such as wrinkles, makeup, shadowing, etc.
- Hair style and color
- Eyebrow shape and color
- Eye shape and color
- Nose shape
- Mouth shape and lip color
- Glasses, facial hair, and face mole
- Body mass
- Favorite color
On the Nintendo Switch version, some features are shuffled around, meaning head shape, skin color, and facial details are grouped together under "Face", for example. The following is the list of features in this version of Mii Maker:
- Facial hair
- Favorite color
This version of Mii Maker also removes the birthdate and creator name, which also applies to every Mii character created in the Nintendo Switch version of Miitopia or received from "Popular" in the same version. This allows any player to modify any Mii they received from other people, unlike the Nintendo 3DS version which limits Mii modification by creator identification.