An SZS file is a game data archive used by Nintendo Switch games, such as Mario Kart 8 Deluxe and Splatoon 2. It typically contains 3D model and texture files used by a Switch game and is compressed using the Nintendo Yaz0 compression format. SZS files are often modified by the homebrew and modding communities to alter the appearance of characters and objects in Switch games.

You can extract the contents of SZS files using Uwizard in Windows. You can also use MK8Snitch for decompressing, editing, and recompiling SZS Mario Kart 8 Deluxe SZS files. NOTE: SZS files are also commonly used to store game data for Nintendo Wii and GameCube games. However, Switch SZS files may not be compatible with programs that open the Wii or GameCube SZS formats.

Data file used by games for the Nintendo Wii; most commonly known for storing 3D model and texture data for the Wii game Mario Kart, but also used by other games for the same kinds of data as well as other types of data; sometimes modified by the homebrew and modding communities to create custom Mario Kart graphics.

SZS files for Mario Kart are stored in a format called the U8 archive format and they are compressed with a method called Yaz0 compression.