JavaScript SDK

The JavaScript/TypeScript SDK is engine agnostic and can be used with any game engine or framework that supports WebSockets, such as:

Modern web browsers (and mobile web browsers)
Node.js
Bun
Electron
React Native
Engines/Frameworks: Phaser, PlayCanvas, React, Pixi.js, Babylon.js, THREE.js, KAPLAY, etc.

Install package

If you’re using a build tool (vite, webpack, rollup, or similar):

npm install --save @colyseus/sdk

pnpm add @colyseus/sdk

yarn add @colyseus/sdk

bun add @colyseus/sdk

Include directly from unpkg. Replace @x.x.x with a version compatible with your server:

<script src="https://unpkg.com/@colyseus/sdk@^0.17.0/dist/colyseus.js"></script>

Download the release binaries from GitHub Releases and include them in your project:

<script src="colyseus.js"></script>

Create a Client instance pointing to your Colyseus server:

import { Client } from "@colyseus/sdk";
 
const client = new Client("http://localhost:2567");

Use https:// for secure connections in production.

Navigate to the Client SDK for API Reference, and select the JavaScript tab.

Client SDK API Reference - Full API documentation for all methods, events, and room operations
State Sync Callbacks - Listen for state changes
Phaser Tutorial - Complete game example