LaunchBox Built-in Command Line Variables

These built-in variables can be used across LaunchBox wherever command line arguments are accepted, including emulator settings, game-specific overrides, and more.

%romfile%

Description: Outputs the ROM file path depending on emulator settings:

• Default: Full path to the ROM file, including quotes.

• If Don't Use Quotes is checked: Outputs the path without quotes.

• If Use File Name Only Without File Extension or Folder Path is checked: Outputs just the bare filename.

Note: If omitted, the ROM file will be placed at the end of the command line.

%platform%

Description: Outputs the game's platform name.

%launchboxorbigboxexepath%

Description: Outputs the full path to either LaunchBox.exe or BigBox.exe, depending on which one is currently running.

%gameid%

Description: Outputs the unique GUID for the game as stored in the XML data.

%romlocation%

Description: Outputs the path to the ROM location, including quotes. Example: "C:\Games\ROMs\NES"

%romfilename%

Description: Outputs the filename of the ROM without its file extension. Example: SuperMarioWorld

%romextension%

Description: Outputs just the file extension of the ROM. Example: .zip, .cue, etc.

%romlocation_noquotes%

Description: Outputs the ROM location path without surrounding quotes.

%noromfile%

Description: Replaced with an empty string. Prevents LaunchBox from automatically appending the ROM file to the end of the command line.

Note: This list may expand with future LaunchBox updates. If you're building plugins or integrating external systems, always test your arguments to ensure correct substitution.