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Live Code Compiler

Write HTML, CSS, and JavaScript with a live preview — free, no signup required.

HTML
CSS
JavaScript
Preview

What is a Live Code Compiler?

A live code compiler (also called a playground or sandbox) is a browser-based editor that lets you write HTML, CSS, and JavaScript and immediately see the rendered result in a preview pane. There's no setup, no build step, and nothing to install — everything runs locally in your browser using a sandboxed iframe.

Our tool is designed for quick experiments, learning the basics of front-end development, prototyping UI snippets, testing CSS rules, debugging a JavaScript function, or sharing a quick demo without setting up a local project.

What you can do with this tool

  • Write HTML — Structure your markup in the HTML editor. No need for <html>, <head>, or <body> boilerplate — just the content you want to render.
  • Style with CSS — Add any valid CSS. Selectors target the HTML you wrote above.
  • Add JavaScript — Write vanilla JS that runs against the rendered DOM. Use console.log() to debug (output appears in your browser's DevTools console).
  • Live preview — Click Run to execute and see the result in the preview pane on the right.
  • Clear — Reset all three editors with one click.

How to use the compiler

  1. Type or paste HTML into the HTML editor.
  2. Add CSS rules in the CSS editor to style your markup.
  3. Add any JavaScript you want to run on page load in the JavaScript editor.
  4. Click the Run button. The iframe preview refreshes instantly with your combined output.
  5. Use Clear to wipe all three editors and start fresh.

Who is this for?

  • Students & beginners learning HTML/CSS/JS without installing a code editor.
  • Front-end developers testing a snippet, a selector, or a layout idea in isolation.
  • Interviewers & candidates running quick coding exercises during a technical screen.
  • Writers & teachers demonstrating a concept with a working example.

Privacy & safety

Your code never leaves your browser. Nothing is uploaded to a server, logged, or tracked. The preview runs inside a sandboxed iframe (sandbox="allow-scripts"), so any JavaScript you execute is isolated from the rest of the page.

Frequently Asked Questions

No. All editing and execution happens entirely inside your browser. Your code is never uploaded, logged, stored on our servers, or shared with any third party. Refreshing the page will clear your work, so copy anything you want to keep before closing the tab.
The tool supports HTML, CSS, and JavaScript — the three core languages of front-end web development. You can use modern ES6+ JavaScript, CSS3 features (flexbox, grid, custom properties), and standard HTML5 markup. Server-side languages like Python, PHP, or Java are not supported because the compiler runs entirely in your browser.
Yes. Add a <script src="https://cdn..."></script> or <link rel="stylesheet" href="..."> tag inside the HTML editor pointing to a public CDN (such as unpkg, jsdelivr, or cdnjs). The library will load when you click Run and you can use it inside your HTML or JavaScript.
Open your browser's Developer Tools (F12 or Right-click → Inspect → Console tab) to see any console.log(), console.warn(), or console.error() output from the iframe. The preview pane itself only shows the rendered DOM, not console messages.
Make sure you clicked the Run button after editing — the preview does not auto-refresh. Also check your browser's console for syntax errors. If you're trying to access DOM elements that haven't been added yet, wrap your code in a DOMContentLoaded listener or place the script after the relevant markup.
There's no built-in export yet. You can manually copy the contents of each editor into a local .html, .css, or .js file. For a single-file setup, paste the CSS inside a <style> tag and the JS inside a <script> tag in your HTML file.