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Dev tools · December 17, 2018

RunJS

The JavaScript playground for your desktop

RunJS launched on December 17, 2018 with 18 votes, #680 of 2,148 launches that month and more than 50% of that year's launches. The site was still online in September 2026, 7 years on.

What it does

RunJS is a modern JavaScript and TypeScript playground, displaying instant results as you type and providing access to Node and browser APIs.

Live results as you type. Built-in Node.js and browser environments, install npm packages, prototype UI live - no project, no setup, no signup. Mac, Windows, Linux.

RunJS is a scratchpad where code runs as you type. Node.js, browser and npm - all in one place. With RunJS you have built-in Node.js and browser environments . This gives you a level of versatility that's not possible in the Node REPL or the Chrome console. Exploring JavaScript has never been easier. Whether it's learning, completing code challenges or creative experimentation, RunJS is the perfect playground for all your JavaScript adventures. Inspect any value, without modifying your code. Use Magic Comments and Logpoints to log any value, no console.logfrom runjs.app

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