Installing

OpenGTA ships as one WebAssembly module, opengta.wasm, plus ready-to-run bundles of that module with gasm's native runner gasm-run for macOS, Linux and Windows. None of them contains any of the game: you need your own copy of GTA from Rockstar's 2002 re-release (GTAINSTALLER.zip), see Game data. OpenGTA is early work: read Status first.

Download a bundle

Each release has:

System	File	Start
macOS 11 or later (Apple Silicon and Intel)	opengta-gasm-<version>-macos-universal.zip	OpenGTA (gasm).app
Linux x86_64 / arm64	opengta-gasm-<version>-linux-<arch>.tar.gz	./opengta.sh
Windows x86_64	opengta-gasm-<version>-windows-x86_64.zip	OpenGTA.cmd
any system with gasm-run 0.6.0 or newer	opengta-<version>.wasm	gasm-run opengta-<version>.wasm --asset-dir <your GTA>

Every file has a .sha256 next to it. To check a download:

shasum -a 256 -c opengta-gasm-0.1.0-macos-universal.zip.sha256     # macOS
sha256sum -c opengta-gasm-0.1.0-linux-x86_64.tar.gz.sha256          # Linux

On Windows: Get-FileHash opengta-gasm-0.1.0-windows-x86_64.zip in PowerShell, and compare with the .sha256 file.

Unpack the archive anywhere. Each bundle has a README.txt with the same instructions as this page.

First run: choose your game data

The first time, the launcher asks where your GTA is. Either folder works:

• the installed game: the folder the Windows setup installed GTA to, with GTADATA and WINO in it (and WINO/Grand Theft Auto.exe, which must be the re-release's, 774,144 bytes);
• the unzipped installer: the folder you unzipped GTAINSTALLER.zip to, with data1.cab and data2.cab. There is no need to run its setup, so this is the easy way on macOS and Linux.

The launcher checks the folder and says what is missing if it is neither. The zip itself doesn't work: unzip it first. Your choice is remembered, and the next start goes straight to the game.

	macOS	Linux	Windows
How it asks	a dialog, then a folder chooser	zenity or kdialog, if installed; otherwise pass the folder: ./opengta.sh /path/to/GTA	a dialog, then a folder chooser
Saved in	~/Library/Application Support/OpenGTA/data-location	~/.config/opengta/data-location	%APPDATA%\OpenGTA\data-location
Choose again	hold Option while opening the app	./opengta.sh --change-data	OpenGTA.cmd --change-data
Log	~/Library/Logs/OpenGTA/gasm.log	the terminal, or ~/.local/state/opengta/gasm.log when started from a menu	the console window and %LOCALAPPDATA%\OpenGTA\gasm.log
Saves	~/Library/Application Support/gasm/opengta/	~/.local/share/gasm/opengta/	%APPDATA%\gasm\opengta\

The saves (player names, scores, options) are gasm's storage for opengta, the same namespace the browser player uses in the browser.

Launcher options

All three launchers take the same options:

opengta.sh [options] [DATA] [gasm-run options...]

Option	What
DATA	the game folder for this run; it is saved for the next ones
--change-data	ask for the game data even if a location is saved
--forget-data	delete the saved location and exit
--dry-run	print the gasm-run command instead of running it
--install-desktop	(Linux) add a menu entry, ~/.local/share/applications/opengta-gasm.desktop
--help	the options and where things are kept

Anything after the data goes to gasm-run: launch parameters like --param intro=0 or --param mission=1, and the runner's own options such as --window 1280x960, --filter nearest or --mute (see Running on gasm). On macOS, from Terminal:

"OpenGTA (gasm).app/Contents/MacOS/OpenGTA" --param intro=0
open "OpenGTA (gasm).app" --args --change-data

OPENGTA_DATA=<folder> uses that folder for one run without saving it, and makes a missing or wrong folder an error (exit code 2) instead of a dialog: that is how the bundles are tested.

macOS: Gatekeeper

The app is signed ad hoc, not notarized by Apple, so the first start is blocked as from an "unidentified developer". Right-click (or Control-click) OpenGTA (gasm).app and choose Open, then Open again. On macOS 15 and later, open it once, then go to System Settings > Privacy & Security and click Open Anyway. Or remove the quarantine flag that the download added:

xattr -dr com.apple.quarantine "OpenGTA (gasm).app"

Linux: libraries

gasm-run needs ALSA for sound (libasound2; the package is libasound2t64 on Debian 13, Ubuntu 24.04 and newer) and a Vulkan capable graphics driver for the window. For the folder chooser, install zenity (GNOME) or kdialog (KDE), or pass the folder as an argument once.

Windows: SmartScreen

gasm-run.exe and the launcher are not signed. If Windows SmartScreen says it protected your PC, click More info, then Run anyway. If Windows marks the downloaded zip as coming from the internet, you can also unblock it before unpacking: right-click the zip, Properties, tick Unblock. OpenGTA.cmd runs opengta.ps1 with PowerShell (built into Windows); a window stays open after an error so you can read it.

In the browser

Nothing to install: open the player. See Playing in the browser.

From source

See Build from source.