RunJS LogoRunJS

The Offline JavaScript Sandbox

Web Audio

Other platforms

Explore JavaScript, access Node and Browser APIs, get instant feedback as you type, install NPM packages and much more.

Navigating the JavaScript ecosystem can be complicated. From bundlers to transpilers to package managers, there's a lot to know and a lot to set up before you can even begin to start writing code. RunJS makes it easy, one app, zero configuration needed, simply an isolated space for you to focus on writing code with instant results.

RunJS is free for you to download and use. If you'd like to do more with RunJS, such as installing NPM packages, opening multiple tabs, creating snippets, using language services and much more, purchase a license and get unlimited access to all features.


Latest version: 2.7.3

macOS (.app)Universal
Windows (.exe)64 bit
Linux (.deb)64 bitARMARM 64
Linux (.tar.gz)64 bitARMARM 64

Built with simplicity in mind

All Equal

Reduce the feedback loop between writing and running your code. Get live results as you type.

A JavaScript playground for your desktop. Perfect for testing the latest JavaScript features and libraries. This is my go-to app for playing around with JavaScript. 👌🏻
Amit Merchant

Amit Merchant

Whether you're a beginner just starting out or a seasoned coder, tinkering with code can be a great way to learn and level up.

Pipe Operator
Really impressed with Javascript scratchpad tool RunJS. Useful while learning new concepts and trying it out.
Ujval Joshi

Ujval Joshi

NPM integration makes trying out new libraries quick and easy.Premium

Woah, here's a slick way to learn/experiment/teach JavaScript: RunJS. - Compiles via Babel - TypeScript support - Reference npm packages - Runs your code on every keystroke
Cory House

Cory House

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Go on, give it a try.