Quick Summary
JavaScript Online Viewer is an in-browser console sandbox and code formatter that captures console.log outputs, checks JS syntax errors, and minifies scripts locally.
What it does
Live console output
Execute JavaScript functions locally and capture return values and console logs in real time (Alt+1).
JS Beautifier
Format messy or minified JavaScript files into clean 2-space indented source code (Alt+3).
Syntax Check & Minifier
Check for JS syntax errors and compress code by stripping comments and unneeded spaces (Alt+2).
Frequently asked questions
Can I test async/await and promises in the JS sandbox?
Yes, modern browser ES6+ features including promises, async/await, and arrow functions are supported.
How are console.log statements displayed?
All console.log(), console.warn(), and console.error() outputs are intercepted and displayed sequentially in the Console Logs pane.