.DSZ File Extension

DeSmuME is a Nintendo DS emulator that allows gamers to play DS games on their PCs. DS Player is a WebAssembly version of DeSmuME, which can be used to play DS games on an iPhone or iPad.

By default, DS Player automatically saves players' saved game data in its own local storage. However, a player can also export their current saved game data as a DSZ file, by selecting the Backup button found in the Save Data section of DS Player's menu.

Exporting their saved game as a DSZ file allows a player to retain the saved game even if they delete DS Player from their Home screen. It also allows the player to transfer their saved game data to the PC versions of DeSmuME (by extracting and loading the DSV file the DSZ file contains).

You can open a DSZ file with DS Player. Before doing so, make sure you have access to the game ROM (likely an .NDS file) that was used to create the DSZ file. Then:

1. Open DS Player.
2. Load your game ROM (using the Choose File button).
3. Open DS Player's menu (by pressing M).
4. Select Restore → Choose File.
5. Navigate to and load your DSZ file.

At this point, DS Player will show you a Save data updated message. Select Close to close that message, and then close and re-open DS Player. Load your game ROM again, and your saved game will load in DS Player.

To use a DSZ file with the PC versions of DeSmuME:

1. Rename the file's extension to .zip (instead of .dsz).
2. Use any Zip-decompression utility to extract the DSV file your new ZIP file contains.
3. If necessary, add the .dsv extension to the extracted file.

Then, you can load your DSV file as you would any other DeSmuME DSV file.