Free browser 3D games — no download, built with Three.js
A dozen native WebGL / Three.js 3D games that play instantly in your browser. Zero installs, zero signup, zero waiting. Around the games sit free companion tools: a HoYoverse gacha probability calculator, a CC0 3D asset library, AI pet portraits, and AI talking-head video.
What is MetaWorldOS?
etaWorldOS is a home for native browser 3D games. Every title is built with Three.js on top of WebGL 2 — no Unity WebGL export, no cross-compiled runtime, no 40 MB download before you can hit "play". A link opens a working 3D game in under a second on a modern connection. Rhythm racing, tower defense, snooker, tank battles, snake-crossroad, and more are already live in the Game Center.
Native web means the games are also portable to anyone with a browser: shared leaderboards across desktop and mobile, one URL to send a friend, touch controls that activate automatically on phones, and graphics quality that auto-scales to hardware. WebGL for rendering, Web Audio for sound, WebAssembly for physics where it matters — a single stack that we've been sharpening one game at a time.
Alongside the games we ship free companion tools built with the same math discipline: an exact-Markov-chain HoYoverse gacha calculator (Genshin, Star Rail, ZZZ), a CC0 / CC-BY 3D asset library that exports GLB for Unity, Unreal 5, Godot 4, and Three.js, and a couple of AI creative helpers. If you like reading how things are built, the engineering blog documents every non-trivial system — the Keplerian solar system in 700 lines, real-time meteor showers, a client-side SGP4 satellite tracker.
Explore what you can do here
Game Center — Free Browser 3D Games
A dozen native Three.js / WebGL 3D games — rhythm racing, tower defense, snooker, snake-crossroad, tank battles. Instant play, shared leaderboards, no download, works on desktop and mobile.
Free 3D Game Assets (GLB)
CC0 & CC-BY 3D asset library — characters, props, vehicles, scenes. In-browser Three.js preview, direct GLB download. Works in Unity 2022+, Unreal 5, Godot 4, and Three.js.
GameTool
A growing set of free single-purpose tools for gamers and indie devs — HoYoverse gacha probability calculator (Genshin / HSR / ZZZ), Kepler equation solver, TLE decoder, moon phase.
Latest from the engineering blog
How Infinitown fakes an infinite city with 81 chunks and mod 9
The infinite-scrolling town in our Infinitown gamecenter port isn't procedurally generated — it's a Möbius carpet. A 9×9 pool of pre-built chunks maps onto a 9×9 grid of fixed container slots through modulo arithmetic, and camera drags rebind slots to different pool entries instead of spawning new geometry. This post walks the four moving parts (pool, containers, mapping, drag event) and explains why the whole system holds together with zero allocations at runtime.
Four bugs that all looked like shadow acne
A road-surface flicker in our Infinitown gamecenter port survived every shadow-parameter tweak we threw at it — bias, normalBias, PCF radius, a 4096² shadow map, snap-tracked light. It turned out to be four separate depth-buffer bugs stacked on top of each other, only the last of which was a shadow problem. This is the debugging log — what we tried, what the symptom kept telling us, and the diagnostic toggles that finally isolated each layer.
A four-anchor raycast suspension for a tank in raw Rapier
Tank Battle's chassis rides on four downward raycasts, each of which contributes a spring impulse, a track-drive impulse, and a lateral friction impulse. It's the standard raycast-vehicle pattern from Unity's Wheel Collider or BeamNG, written straight against @dimforge/rapier3d-compat with no vehicle plugin. Here's the whole loop, the constants, the front/rear drive split, and the lateral-friction cliff that makes it feel like a tank.
Frequently asked questions
Q01Can I play 3D games in the browser without downloading anything?
Yes. Every game in the MetaWorldOS Game Center is a native browser game built with Three.js on WebGL 2. Nothing to install, no plugin, no Unity WebGL bootstrap — the whole game loads over a normal HTTPS request in under a second on a broadband connection and starts running immediately. Free tier requires no account.
Q02What is Three.js and why is it fast enough for real games?
Three.js is a JavaScript library that wraps WebGL 2, the browser's native GPU API. It gives you the same underlying GPU access as Unity or Unreal — hardware instancing, PBR materials, post-processing — but ships zero runtime download because the browser already has WebGL. On mid-range hardware you get a stable 60 fps for the kind of games in our Game Center (a few thousand draw calls, streaming asset loads).
Q03Do these browser 3D games work on mobile phones?
Yes. Every game auto-detects mobile Safari, mobile Chrome, and in-app browsers, then enables touch controls, halves the render resolution when needed, and lowers post-processing to hit 60 fps on mid-range Android and any recent iPhone. No separate app version — the same URL works everywhere.
Q04Are the games really free? Any ads or accounts?
The full Game Center is free with no ads inside gameplay. An account is optional — you only need one to submit to shared leaderboards or sync progress across devices. Sign-up is one form field, no email verification loop.
Q05What else is on the site besides the games?
Three free companion tools: (1) a HoYoverse gacha probability calculator at /tools/mihoyo-gacha covering Genshin Impact, Honkai: Star Rail, and Zenless Zone Zero with exact Markov-chain math; (2) a CC0 / CC BY 3D game asset library at /game-assets that exports GLB files ready for Unity, Unreal 5, Godot 4, and Three.js; (3) two AI creative tools — pet portrait generation and talking-head video. The games are the flagship; everything else is companion.
Q06How are the games built? Is there a technical write-up?
Yes. The engineering blog documents every non-trivial system we ship: the 700-line Keplerian solar system, real-time meteor showers in WebGL, an SGP4 satellite tracker running client-side, and per-game breakdowns of physics, camera, and shader work. If you're curious about doing this yourself, the blog is the fastest primer.