A Unity alternative for small web games
For a small game that should open instantly from a link and run on phones, a web-native engine usually beats a Unity web build: smaller downloads, no long first load, and JavaScript you can change and reload in seconds. The open options are three.js (renderer), Babylon.js and PlayCanvas (full engines), Phaser (2D) and GDevelop (no-code).
GrowBlocks is the one that also gives you characters, multiplayer rooms, hosting and a player audience, and it is built to be programmed by AI assistants. We measured the difference by building the same game in both: GrowBlocks vs Unity 6 WebGL.
Why Unity can feel heavy on the web
Unity exports to the web through WebGL (and newer WebGPU support), and it is excellent for big projects and for shipping the same game to consoles, PC and mobile stores. For a small browser game, the trade-offs are a larger first download, a slower start on phones, and a C# build step between every change and the result.
The web-native options
| Option | What it is | Good for |
|---|---|---|
| three.js | Open-source 3D renderer | Full control; you add physics, input and networking |
| Babylon.js | Open-source 3D engine with physics plugins | Feature-rich 3D in the browser |
| PlayCanvas | Open-source engine with a hosted visual editor | Teams who want an editor and the web |
| Phaser | Open-source 2D framework | 2D browser games |
| GDevelop | Open-source no-code engine | Making games without code |
| GrowBlocks Dev Kit | Hosted platform on three.js + Rapier | 3D multiplayer games built fast, often with an AI assistant, played by GrowBlocks players |
What a GrowBlocks game looks like
export default async function game(gb){
gb.world.style('sunset');
gb.world.ground({size:60});
gb.world.box({size:[1,1,1], position:[0,4,-4], color:'#ff5fa2', physics:'dynamic'});
gb.player.spawn({position:[0,1,6]});
const room = (await gb.net.join()).showPlayers();
}No renderer, scene, camera or loop to create, no bundler, no npm packages inside the game: game.js exports one function and the engine runs it.
Start
npx growblocks new my-game
cd my-game
npx growblocks dev # play it at http://localhost:5173/play.htmlWhen this is the wrong choice
The engine is licensed for games published on GrowBlocks only. You cannot export a GrowBlocks game to Steam, an app store or your own server, and you cannot self-host the engine. Your game code and art stay yours (terms).
If you need console or app-store builds, stay with Unity or Godot. If you want an open-source engine you control end to end, pick Babylon.js, PlayCanvas or three.js.
Questions people ask
- Is Unity good for browser games?
- Unity can build for the web, and it is strong for large cross-platform projects. For small games that must load quickly on phones, web-native engines are usually lighter.
- What is the lightest way to make a 3D browser game?
- Start from three.js, or from a framework on top of it such as the GrowBlocks Dev Kit, which already includes physics, characters and multiplayer.
- Can GrowBlocks games run on phones?
- Yes. Games that read gb.input.move and gb.input.action get touch controls automatically.
Try it in five minutes
npx growblocks new my-gameKeep reading
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