Downloads
Download the test client for Windows and start it through Launcher.exe.
New MU Online client with launcher
An auto-updating launcher, improved graphics and a strong focus on performance. Adjust resolution, graphics quality and the FPS limit in the launcher to suit your computer.
Download the new client · 728.5 MB
Download BETA client (v23, 2026-09-30, 728.5 MB)
The new client is actively developed. Report problems in the website chat with the client version and steps to reproduce; crash reports are sent automatically.
How to install and start playing
- Create a MuMat account on the website.
- Download the complete archive and extract it into a separate folder. Keep all client files together.
- Run Launcher.exe from the extracted folder. On Linux, run it through Wine using the guide below.
- Choose Main in the launcher, wait for updates, then sign in with your MuMat account and start the game.
MU Online on Linux and MacBook
Linux: the new client has been tested through Wine, including launching from Launcher.exe into the game. Use an up-to-date Wine installation and working graphics drivers.
MacBook / macOS: CrossOver is a possible way to try the Windows client on Intel or Apple Silicon. MuMat has not yet been tested on a real Mac; a working launcher alone does not confirm that the game works.
If the client does not start or connect
Check that the archive was fully downloaded and extracted. Run Launcher.exe from the client folder, rather than from inside the archive.
Allow the launcher to finish updating. In the BETA, also check that Main is selected for mumat.net.
If the problem remains, ask in the website chat and include the client version, the error message and the step where it occurs.