Open olivers.tools/play and join a room of up to 12 players in Super Mario 64, with live video chat. It was announced on X by olivers_tools, who says it is built on sm64coopdx and sm64ex and runs on a central server instead of on one player's machine. Whether it asks for your own ROM, and whether the source is public, is not stated in the posts.
From the creator
I built Super Mario 64 as Multiplayer with up to 12 players.
— olivers_tools (@olivers_tools) October 7, 2026
Everyone can roam around the entire game, every level, or play the original missions together.
All in the browser and including live video chat.
I am right now in the game testing it out, join me if you like:
https://olivers.tools/play
The original game
Bowser kidnaps Princess Peach and hides the castle's 120 Power Stars in paintings. Mario collects the Stars to reach Bowser and rescue her. The game holds 94/100 on Metacritic and sold nearly 12 million copies by 2015, making it the best-selling Nintendo 64 game.
Directed and produced by Shigeru Miyamoto. Super Mario 64 on Wikipedia
The browser version
olivers_tools announced the project on X as Super Mario 64 as multiplayer with up to 12 players. Players can roam the entire game, every level, or play the original missions together, all in the browser and with live video chat. The post links to olivers.tools/play.
A follow-up post names the base: sm64coopdx and sm64ex. sm64coopdx is an online multiplayer project for the Super Mario 64 PC port, with up to 16 players and a Lua modding API; its page says to drag a .z64 ROM onto the program. sm64ex is a fork of sm64-port/sm64-port published under the sm64pc account. The creator writes that coopDX normally runs on one of the participants and had to be modified to run on a central server.
The creator lists three mods of their own: better mobile support, a shooter mode, and running on the server with technically hundreds of players, capped at 12 per room for now.
A later post lists new features: invites into private rooms, leaderboards for stars, coins, kills and deaths, new characters (Bowser Jr., Kong, Yoshi, Luigi, Wario, Toad), playing the whole map unlocked or starting fresh, custom key bindings, muting other players, and a redesigned onboarding. It also mentions playing inside the X timeline, which the creator says is still to be tested.
The posts do not say how the game runs in the browser tab, whether it needs your own ROM, or where the source code is.
| Base | sm64coopdx and sm64ex (named by the creator) |
|---|---|
| Players | Up to 12 per room (the server could hold more, per the creator) |
| Modes | Roam every level, or the original missions; a shooter mode |
| Extras | Live video chat, private rooms, leaderboards, extra characters, key bindings, mobile support |
| Game data | Not stated |
| Source code | Not linked in the posts |
| Browser technology | Not published |
How to play it
- Open olivers.tools/play in a browser.
- Join a room, or invite people into a private one.
- Choose between the whole map unlocked or a fresh start.
- The posts do not say whether a ROM is needed. If the page asks for one, use a copy of your own.
Links
Source code
Questions
Can you play Super Mario 64 multiplayer in a browser?
Yes. olivers.tools/play offers rooms of up to 12 players in a browser tab, according to the creator's posts.
How many players fit in a room?
Twelve per room for now. The creator says the server can technically handle hundreds of players. sm64coopdx on its own supports up to 16.
Is it recompiled or decompiled?
It is built on sm64coopdx and sm64ex, which come from the Super Mario 64 PC port, itself based on the fan decompilation. How the game runs in the browser has not been published.
Do I need to own Super Mario 64?
The posts do not say. sm64coopdx itself asks for a .z64 ROM of your own.
Does it have voice or video chat?
Yes. The launch post says live video chat is included, and a later post adds the option to mute other players.
Is it official?
No. Super Mario 64 is by Nintendo; this is a fan project. Nintendo has had other Mario 64 fan projects removed, so the page could disappear.
Sources and coverage
- olivers_tools on X: launch post
- olivers_tools on X
- sm64coopdx
- sm64pc/sm64ex on GitHub
- Super Mario 64 on Wikipedia
Details checked 2026-10-08. Fan projects change fast; check the project page for the latest.