What exporting a .mii file means and when you need it

A .mii file is a data file that stores the appearance and settings of a Mii character — the customizable avatar you create on Nintendo systems. Exporting saves that character as a file you can transfer to another console, share with someone else, or back up for safekeeping. The steps differ depending on which Nintendo system you own and what you want to do with the file afterward.

You might export a Mii if you're moving to a new console, want to use the same character across multiple devices, or need to send it to a friend. The process takes just a few minutes once you know which method applies to your situation.

Key Takeaways

  • Nintendo Switch exports Miis through the Mii Studio app, which saves them as .mii files you can share or transfer.
  • Wii and Wii U systems require you to copy the Mii to an SD card using the system's built-in Mii Channel or Mii Maker.
  • 3DS systems let you export Miis through Mii Maker, which creates a file you can move to an SD card.
  • Once exported, you can import the .mii file into another console of the same type or share it digitally with others.

Exporting a Mii on Nintendo Switch

On Switch, open the Mii Studio app from your home screen. Select the Mii you want to export, then choose "Edit" or the menu option for that character. Look for an option labeled "Export" or "Save as file" — the exact wording varies by firmware version. The system will save the Mii as a .mii file to your console's internal storage.

To access the exported file, you'll need to connect your Switch to a computer using a USB-C cable and enable file transfer mode. The .mii file will be in a folder structure on the console's storage. Once you have the file on your computer, you can email it, upload it to cloud storage, or copy it to another Switch console by reversing the process.

Exporting a Mii on Wii or Wii U

On the original Wii, go to the Wii Menu and open the Mii Channel. Find the Mii you want to export, select it, and look for an option to "Copy" the character. You'll be prompted to copy it to an SD card — insert an SD card into the Wii's slot and confirm. The Mii is now saved as a .mii file on that card.

On Wii U, the process is similar but uses Mii Maker instead of the Mii Channel. Open Mii Maker from the home menu, select your Mii, and choose the option to copy or export it to an SD card. Once the file is on the card, you can remove the card and read it on a computer or insert it into another Wii or Wii U console to import the character.

Exporting a Mii on Nintendo 3DS

On 3DS systems, open Mii Maker from the home screen. Select the Mii you want to export and look for an option to "Copy" or "Export." The system will save the character to your SD card as a .mii file. You can then remove the SD card from the 3DS and access the file on a computer.

The .mii file will be stored in a specific folder on the 3DS SD card. If you're moving the file to another 3DS, simply insert the SD card into the new system and import the Mii through Mii Maker. If you want to use the Mii on a different type of console — like a Switch — you'll need to recreate the character manually, as .mii files from 3DS are not directly compatible with Switch.

Where .mii files are stored and how to find them

On Switch, exported Miis are stored in the console's internal storage in a folder structure that requires a computer connection to access. On Wii, Wii U, and 3DS, the files go directly to the SD card, making them easier to locate and transfer. Once you remove the SD card and connect it to a computer, the .mii file will be in a folder labeled something like "Mii" or "Nintendo" depending on the system.

File names are usually auto-generated with numbers or the Mii's name. Keep track of which file belongs to which character if you're exporting multiple Miis. Renaming the file on your computer won't affect whether it can be imported into a console, but clear names make it easier to organize.

Importing an exported .mii file into another console

To import a .mii file, the process reverses the export steps. On Switch, copy the .mii file back to the console's storage using a USB connection, then open Mii Studio and select "Import." On Wii, Wii U, or 3DS, insert the SD card containing the .mii file and open the Mii Channel or Mii Maker, then choose the import or copy option.

The imported Mii will appear in your Mii list with the same appearance and settings as the original. You can then use it in games, as your profile avatar, or export it again if needed. Importing does not delete the original file from the SD card or console storage, so you can import the same Mii to multiple systems.

Sharing .mii files with other people

Once you have a .mii file on your computer, you can share it with others via email, cloud storage services like Google Drive or Dropbox, or file-sharing platforms. The person receiving the file will need a compatible Nintendo console and the ability to transfer files to that console's SD card or internal storage.

Make sure the person you're sharing with has the same type of console — a .mii file from a Wii won't import into a Switch, for example. If they have the right system, they can download the file, transfer it to their console, and import it using the same steps you used to import it yourself.

Frequently Asked Questions

Can I use a .mii file from a Wii on a Nintendo Switch?

No, .mii files are not directly compatible across different console types. You would need to recreate the Mii manually on the Switch using Mii Studio, matching the appearance of the original character as closely as possible. However, you can use .mii files between systems of the same type — for example, from one Wii to another Wii.

What do I do if the export option doesn't appear in Mii Studio?

Make sure you're running the latest system software on your Switch. Older versions of the Mii Studio app may not have the export feature. Check for system updates in Settings, then try opening Mii Studio again. If the option still doesn't appear, the app may need to be updated separately through the eShop.

Can I edit a .mii file on my computer before importing it?

Not directly — .mii files are binary data files that can't be edited in standard text editors or image programs. You would need to import the file into a console, edit the Mii's appearance there, and then export it again if you want to make changes.

Will importing a .mii file overwrite my existing Mii?

No, importing creates a new Mii in your list. The original Mii remains unchanged. If you import the same .mii file multiple times, you'll end up with duplicate Miis on your console, which you can delete individually if needed.

Where can I find .mii files that other people have created?

Some gaming communities and fan sites host collections of .mii files for download, though availability varies. You can also ask friends or online communities to share .mii files directly with you. Always download files from sources you trust, as with any file from the internet.