.SFS File Extension

A .SFS file is a Squashfs File Archive, created by Squad.

Open with Squad Kerbal Space Program. Available for Linux, Windows, and Mac.

What is a .SFS file?

A .SFS file is a type of file used by the video game Kerbal Space Program, which is a game where players design, build, and launch rockets into space. The file extension .SFS stands for Squashfs File Archive, but in the context of Kerbal Space Program, it specifically refers to saved game files.

These saved game files, such as the primary file named "persistent.sfs," store the current state of the player's game. This includes all ongoing rocket flights and any modifications made to the game scenario. The content of an SFS file is in plain text and uses a format similar to JSON, which is a way of organizing data using keys and values. This makes it relatively easy for players who are modifying the game (modders) to read and edit the file.

For example, by editing the "persistent.sfs" file, a player could increase their in-game funds, allowing them to build bigger and better rockets. Additionally, players can create and use "quicksave" files, named "quicksave.sfs," to save the game at specific points. This feature is particularly useful if a player wants to return to an earlier state of the game, such as before a rocket crash.

To open and edit .SFS files, players can use several programs: - **Squad Kerbal Space Program**: This is the game itself, which automatically reads and writes these files. - **Text editors**: Simple programs like Microsoft Notepad (included with Windows), Apple TextEdit (included with macOS), or any other basic text editor can open .SFS files for viewing and editing. These are useful for modders looking to manually change game data. - **Vim**: This is a more advanced text editor that can also be used to edit .SFS files, offering more features for complex editing tasks. - **SFSEd**: A specialized tool designed for editing .SFS files, providing features that might be specifically useful for Kerbal Space Program players and modders.

Kerbal Space Program is available on multiple platforms, including Windows, macOS, and Linux, making it accessible to a wide range of players. The ability to edit .SFS files adds an extra layer of customization and control, enhancing the game experience for those who like to tweak and modify their gameplay.


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