RunJS
Write and run JavaScript instantly 🚀
RunJS launched on March 17, 2019 with 2 votes. The site was still online in September 2026, 7 years on.
What it does
RunJS is an awesome JavaScript playground that auto-evaluates your code as you type and outputs the results to a console pane.
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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