HTML Viewer

Preview HTML/CSS code instantly with our live editor.

Live HTML Viewer

HTML/CSS Input Auto-update

<!DOCTYPE html>
<html>
<head><style>body { font-family: sans-serif; text-align: center; padding: 50px; background: #f4f4f9; }
    h1 { color: #3b82f6; }
    .box { background: white; padding: 20px; border-radius: 8px; box-shadow: 0 4px 6px rgba(0,0,0,0.1); }</style></head>
<body>
  <div class="box">
    <h1>Hello World!</h1>
    <p>This is your live preview window.</p>
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</html>

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Why use this tool?

Rapid Prototyping

Test layout ideas in seconds

Debugging

Isolate and fix HTML/CSS issues

Visual Feedback

Adjust CSS and see changes instantly

Client Demos

Share interactive previews without deployment

About the HTML Viewer

This Live HTML Viewer is a fully self-contained web application that allows developers to design, test, and preview HTML/CSS code in real-time. Built with vanilla JavaScript, it runs entirely in the browser with no server-side dependencies. The tool features a split-pane interface with an editable code editor on the left and an interactive preview panel on the right, complete with responsive device simulation (desktop, tablet, mobile views).

Perfect for web developers, designers, students, and educators who need to quickly prototype, debug, or demonstrate HTML/CSS code without setting up complex development environments.

How to Use HTML Viewer

Enter your code in the HTML/CSS input panel (left side)

Preview instantly in the right panel (auto-updates when enabled)

Test responsiveness using device tabs (Desktop/Tablet/Mobile)

Copy code with one click when ready

Key Features:

Code Editor:

Direct HTML/CSS editing with syntax highlighting
Tab key support (2-space indentation)
Auto-save functionality in browser memory

Live Preview:

Real-time rendering as you type
Toggle auto-update on/off
Secure sandboxed iframe prevents conflicts

Device Simulation:

Desktop: Full-width responsive view
Tablet: 768px × 1024px simulation
Mobile: 375px × 667px (iPhone SE size)

Actions:

Run Code: Manually refresh preview
Copy: One-click copy to clipboard
Auto-update: Toggle live preview

FAQs

How can I preview HTML code online?

Use this Live HTML Viewer! Paste your HTML/CSS code and see immediate results. No signup, free, and works directly in your browser.

Can I edit HTML and see changes live?

Absolutely. With “Auto-update” enabled, every keystroke updates the preview. Toggle it off if you prefer manual refresh.

How to share HTML code with preview?

Copy your code using the Copy button, then share. Recipients can paste it into any HTML preview tool or this same viewer.

Does this support external CSS libraries?

Yes! Include CDN links in your <head> section (like Bootstrap, Font Awesome) and they’ll load in the preview.

Is my code safe? Where does it go?

100% client-side. Your code never leaves your browser—it’s processed locally using Blob URLs and iframe sandboxing.