Browser game engines compared: GrowBlocks, three.js, Babylon.js, PlayCanvas, GDevelop and Rosebud
Pick by how much you want to build yourself. three.js gives you a renderer; Babylon.js and PlayCanvas give you open-source engines; GDevelop is no-code; Rosebud turns prompts into games inside its own editor. The GrowBlocks Dev Kit gives you a hosted 3D engine with characters, multiplayer and players already in place, programmed in JavaScript, usually by an AI assistant.
The comparison
| Engine | Type | Physics | Multiplayer | You write | Best for |
|---|---|---|---|---|---|
| GrowBlocks Dev Kit | Hosted platform + engine (three.js, Rapier) | Built in (Rapier) | Built in, rooms up to 16 | JavaScript, often via Claude Code or Cursor | 3D multiplayer games with an audience and no servers |
| three.js | Open-source renderer | Add your own | Add your own | JavaScript | Full control and custom 3D on any site |
| Babylon.js | Open-source engine | Plugins (for example Havok) | Add your own | JavaScript or TypeScript | Feature-rich 3D apps and games |
| PlayCanvas | Open-source engine + hosted editor | Built in | Add your own | JavaScript in a visual editor | Teams that want an editor on the web |
| GDevelop | Open-source no-code engine | Built in | Built in | Events, no code | Beginners and 2D games |
| Rosebud AI | AI game maker | Depends on the game | Not its focus | Prompts, code it generates | Quick prototypes from a description |
Checked 18 October 2026. Products change; if something here is out of date, tell us on X @growblocksxyz.
Where GrowBlocks is different
- Made for AI assistants. The API is one file (llms.txt), the starter kit carries
AGENTS.mdandCLAUDE.md, and a headless checker returns errors plus a screenshot so the assistant can see its work. An MCP server gives Claude Code and Cursor tools to check, push and submit. - Players and identity included. Every player arrives with their own GrowBlocks character, and live games appear on the games page.
- Money built in. Games can have their own NFT collections and coin; the developer gets 70% of their fees. The revenue share is live on Robinhood Chain testnet only, paid in tPLAY test credits. It is not real money yet.
Where GrowBlocks is not the answer
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).
It is also 3D and character-first. For 2D, Phaser or GDevelop fit better; for an editor-led team, PlayCanvas.
Questions people ask
- What is the best engine for 3D browser games in 2026?
- It depends on how much you want to build yourself: three.js for full control, Babylon.js or PlayCanvas for open-source engines, GDevelop for no-code, and the GrowBlocks Dev Kit for hosted 3D multiplayer with characters and players included.
- Which browser game engine works best with AI coding assistants?
- One whose full API an assistant can read in one file and test by itself. The GrowBlocks Dev Kit ships llms.txt, TypeScript types, a headless checker with screenshots and an MCP server for exactly this.
- Which browser engines have multiplayer built in?
- GrowBlocks (rooms up to 16 players) and GDevelop include it. With three.js, Babylon.js and PlayCanvas you add a networking library or server.
Try it in five minutes
npx growblocks new my-gameKeep reading
- How to build a multiplayer 3D browser game with Claude CodeStep by step: use Claude Code (or Cursor) with the GrowBlocks Dev Kit to build a multiplayer 3D game that runs in the browser on PC and phone, then publish it with no servers to set up..
- A three.js game framework with characters, physics and multiplayer built inthree.js is a renderer, not a game engine.
- A Roblox and Fortnite UEFN alternative for game creatorsHow GrowBlocks compares with Roblox and Fortnite UEFN for creators: browser play with no install, JavaScript instead of Luau or Verse, a shared character and market, and a 70% share of the fees your game generates..