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Online JavaScript Compiler – Interpreter and Playground

Edit, run, and debug JavaScript code online for free! Powered by JavaScript that runs in your browser.

Edit the JavaScript modules above or replace them with your own code, then press Run. The program executes in a browser worker and prints console output below the editor.

Use it for modern JavaScript syntax, small module experiments, and debugging without installing Node.js or creating a project.

How to use the online JavaScript runner

  1. Edit main.js, or add another .js module and import it with a relative path.
  2. Press Run to validate the syntax and execute the program in the browser worker.
  3. Read console output and errors, make a change, and run the code again.

What this JavaScript playground supports

  • Modern JavaScript. Run current JavaScript module syntax in the browser.
  • Local modules. Create up to five .js files and import them from main.js.
  • Readable console output. Inspect logged values and syntax or runtime errors.
  • Local autosave. Keep the project in this browser between visits.

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Online JavaScript runner FAQ

Yes. You can edit and run JavaScript without installing anything or creating an account. An account is only needed to create a share link.