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Repair common Windows errors and clear accumulated junk for a smoother, more stable PC - no reinstall needed.Free scan · no reinstallCemu supports several Wii U game formats, not just one. For most users, .wua is the best choice: it is a compressed Cemu archive that can be played directly and is recommended by Cemu for convenient, key-free storage. Cemu can also use .wud, .wux, and extracted RPX-format game folders, but each suits a different workflow.
Quick comparison
| Format | What it is | Best for | Keys | Main limitation |
|---|---|---|---|---|
.wua |
A compressed Cemu Wii U archive | Playing, storage, and backups | Cemu recommends it because title keys are not required | Less convenient for tools that need individual files |
.wud |
A Wii U disc image | Preserving or using a disc dump | Encrypted images may require keys | Large and potentially more difficult to configure |
.wux |
A compressed Wii U disc image | Keeping a smaller disc-image dump | Encrypted images may require keys | Retains the key and compatibility issues of disc images |
| RPX folder | An extracted title containing code, content, and meta |
Installing, inspecting, and modding files | Depends on how the dump was created | Uses many files and requires more folder management |
Cemu’s official FAQ recommends WUA for ordinary use. Its changelog describes WUA as a Cemu-created archive that can be played directly and displayed in the game list.
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What each Cemu format means
.wua: the best general-purpose format
A WUA file is a compressed Wii U archive designed for Cemu. It puts a game’s data into one file, saves space compared with an uncompressed extracted title or WUD image, and is straightforward to move between computers or storage devices.
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.wud: a Wii U disc image
WUD is a disc-image format representing a Wii U game disc dump. It can be useful for preserving a disc dump or for a workflow that specifically expects an image, but it is usually less convenient than WUA for everyday Cemu use.
Encrypted WUD images may require the appropriate keys from the user’s own Wii U. Cemu cannot distribute copyrighted keys; its FAQ explains that users must dump and configure their own keys when necessary.
.wux: a compressed disc image
WUX is a compressed version of a WUD-type disc image. Its main advantage is reduced storage space, but it should not be confused with WUA. A WUX file remains a disc-image workflow, so an encrypted image may still need correctly configured keys.
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Extracted RPX format
“RPX format” usually means an extracted Wii U title rather than one standalone ROM file. The .rpx is normally the game executable inside the title’s code directory.
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Game folder/
├── code/
│ └── game.rpx
├── content/
└── meta/
└── meta.xmlNames vary by game, but the code, content, and meta folders are the important structure. Extracted titles are useful when a modding tool needs direct access to individual files.
Which format should you choose?
- For most players: choose
.wua. It is compressed, convenient, and recommended by Cemu for ordinary use. - For modding or file inspection: use an extracted RPX-format folder if the specific tool requires direct access to
code,content, or other game files. - For disc-image preservation: keep
.wudor.wuxif retaining the original image format matters and your key setup is correctly configured.
There is no universally best format. WUA is best for playing and managing a library; extracted files are often better for modifying a game; WUD and WUX are more appropriate when preserving or using a disc-image dump is the priority.
How to load each format in Cemu
Loading a WUA file
- Open Cemu.
- Add the directory containing the WUA file to Cemu’s configured game paths, using the game-list or path settings available in your Cemu version.
- Refresh the game list if necessary, then select the game.
Cemu’s interface has changed between releases, so the exact game-path label may differ. The important point is that a WUA is normally added as a game-library file rather than installed through the extracted-title installer.
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For an extracted title, update, or DLC, use the installation workflow documented by the Cemu Wiki:
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- Open Cemu.
- Select File → Install game title, update or DLC.
- Open the relevant title, update, or DLC directory.
- Open its
metafolder and selectmeta.xml.
Do not select only the .rpx file when the title is supplied as an extracted directory. The metadata file tells Cemu what is being installed.
Loading WUD or WUX
Add or select the image using the game options available in your Cemu release. If the image is encrypted, Cemu may report missing or invalid keys. That is a key-configuration problem, not something fixed by renaming the file.
Where updates and DLC belong
Keep base games in the directories configured as Cemu game paths. Install updates and DLC through File → Install game title, update or DLC, rather than simply copying their folders into the base-game directory.
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Cemu stores installed updates and DLC, saves, and emulated Wii U system data under its configured mlc01 directory. The Cemu Wiki folder-structure guide explains this layout. Older instructions that tell you to manually copy update or DLC folders directly into mlc01 can produce an incorrect or confusing installation.
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Are saves, graphic packs, and mods WUA files?
No. These are separate from the game container:
- Save data: stored as directories in Cemu’s emulated storage, not as a WUA, WUD, WUX, or RPX file. Cemu exposes a game’s save location through its context menu.
- Graphic packs: use folders and configuration files such as
rules.txt. They are not converted into the game’s container format. See the graphic-pack documentation. - Installed content: updates and DLC are installed into Cemu’s emulated storage rather than treated as ordinary files in the base-game path.
What about ISO, WBFS, WAD, ELF, APP, and WUHB files?
Wii .iso, .wbfs, and .wad files belong to different Nintendo platforms or workflows and are not ordinary Wii U Cemu game formats. An ELF file is also not a substitute for a complete Wii U title. Do not rename one of these extensions to .wua, .wud, .wux, or .rpx; renaming changes only the label, not the underlying data.
Some Cemu releases mention support for additional formats, including NUS .app titles and Wii U homebrew .wuhb files. Treat that support as version-dependent and check the release notes for your installed Cemu build. These are not the main formats to choose for an ordinary commercial Wii U game dump.
Troubleshooting format errors
“The file type is invalid”
- Confirm that the file is actually a Wii U dump, not a Wii or unrelated emulator file.
- Check that its extension was not changed without a real conversion.
- For WUD or WUX, verify whether the image is encrypted and whether the required keys are correctly configured.
- For an extracted title, install
meta/meta.xmlrather than selecting an arbitrary folder or only the RPX executable. - Check whether your Cemu version supports the particular format, especially for less-common containers.
- Consider that the dump may be incomplete or corrupted.
The game appears, but the update or DLC does not
Make sure the base game is in a configured game-path directory and that the update or DLC was installed through Cemu using the correct meta.xml. Also verify that Cemu is using the expected mlc01 location.
The game launches, but a mod does not work
The modding tool may require an extracted title while your game is stored as WUA. Follow the tool’s own format requirements; not every utility can edit or apply changes directly to a WUA archive. Graphic packs are a separate folder-based system and do not require converting the game into another container.
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Can you rename WUD to WUA?
No. Renaming game.wud to game.wua does not convert it. WUA is a distinct Cemu archive format. A genuine conversion or repackaging must be performed by a compatible tool using lawfully obtained game data, and the exact options depend on the Cemu version and the source dump.
Legal and key-management note
Use game data dumped from hardware and software you are legally entitled to use, and do not download or share copyrighted game files or title keys. Encrypted WUD and WUX images may require keys dumped from your own Wii U. Cemu’s official FAQ explains why it cannot provide copyrighted keys.
The Bottom Line
Bottom line: Cemu supports .wua, .wud, .wux, and extracted RPX-format titles. Use .wua for the easiest general-purpose setup, an extracted RPX folder for file-level modding, and WUD or WUX when preserving a disc-image dump is more important than convenience.
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