How do I open an HTML file online and preview it?

Paste HTML code or load a file into the editor, and the rendered preview updates instantly. This makes quick HTML checks and debugging easy without installing any software.

Can I test external CSS and JavaScript in this HTML viewer?

Yes. Standard external resources can load in the preview when allowed by your browser's security policies, so you can test full styling and scripts alongside your markup.

Is my HTML code sent to a server?

No. All rendering runs entirely in your browser. Your HTML never leaves your device, which keeps private or unfinished markup secure.

Does the preview update automatically as I edit?

Yes. The viewer re-renders the preview pane in real time as you type or paste, so you see changes immediately without clicking a refresh button.

Can I edit HTML and copy it back out?

Yes. Edit your markup directly in the editor pane, then use the toolbar Copy button to grab the finished HTML for your project.

Open HTML File Online - HTML Viewer, Editor & Live Preview

Open and preview HTML files online with real-time live preview. Edit and format HTML and test web pages safely in your browser, no upload needed.

HTML Viewer

1484

Editor

Code

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <style>
        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
            margin: 0;
        }
        .card {
            background: rgba(255, 255, 255, 0.2);
            backdrop-filter: blur(10px);
            padding: 2rem;
            border-radius: 1rem;
            box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
            border: 1px solid rgba(255, 255, 255, 0.18);
            text-align: center;
            max-width: 400px;
        }
        h1 { margin-top: 0; }
        button {
            background: white;
            color: #764ba2;
            border: none;
            padding: 0.8rem 1.5rem;
            border-radius: 2rem;
            font-weight: bold;
            cursor: pointer;
            transition: transform 0.2s;
        }
        button:hover {
            transform: scale(1.05);
        }
    </style>
</head>
<body>
    <div class="card">
        <h1>Hello World!</h1>
        <p>This is a live preview of your HTML code.</p>
        <button onclick="alert('It works!')">Click Me</button>
    </div>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <style>
        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            display: flex;
            justify-content: center;
            align-items: center;
            height: 100vh;
            margin: 0;
        }
        .card {
            background: rgba(255, 255, 255, 0.2);
            backdrop-filter: blur(10px);
            padding: 2rem;
            border-radius: 1rem;
            box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
            border: 1px solid rgba(255, 255, 255, 0.18);
            text-align: center;
            max-width: 400px;
        }
        h1 { margin-top: 0; }
        button {
            background: white;
            color: #764ba2;
            border: none;
            padding: 0.8rem 1.5rem;
            border-radius: 2rem;
            font-weight: bold;
            cursor: pointer;
            transition: transform 0.2s;
        }
        button:hover {
            transform: scale(1.05);
        }
    </style>
</head>
<body>
    <div class="card">
        <h1>Hello World!</h1>
        <p>This is a live preview of your HTML code.</p>
        <button onclick="alert('It works!')">Click Me</button>
    </div>
</body>
</html>

Preview

Live Preview

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How to Use HTML Viewer?

Type or paste your HTML code into the editor pane.

The preview pane will update automatically to show the rendered result.

Use the toolbar buttons to Copy, Clear, or Toggle Fullscreen.

Key Features

Real-time Preview

Instantly see how your HTML code renders as you type.

Privacy Focused

Your code never leaves your browser. All processing is done locally.

Responsive Design

Use the split-screen view or go full-screen for a better editing experience.

Paste or open any HTML file and this online HTML viewer renders it instantly in a live preview pane beside the editor—no upload, no install. Edit markup in the browser, watch the rendered output update in real time, and load external CSS and JavaScript to test full web pages. All processing stays local, so your code never leaves your device.

How to Use the HTML Viewer

1
Paste or open your HTML
Type your markup into the editor pane or paste an existing HTML file's contents directly into it.
2
Watch the live preview
The preview pane renders your HTML automatically as you type, showing exactly how the page will look in a browser.
3
Test CSS and JavaScript
Add inline or external <style> and <script> tags to preview styling and interactive behavior in the same view.
4
Copy, clear, or go fullscreen
Use the toolbar to copy your code, clear the editor, or toggle fullscreen for a wider editing and preview workspace.

References

WHATWG — HTML Standard
The living specification defining HTML syntax, elements, and rendering behavior in modern browsers.
MDN — HTML
Comprehensive reference and tutorials for HTML elements, attributes, and best practices.

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Strip whitespace and comments to shrink your HTML for production.

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Markdown Viewer

Preview Markdown rendered as HTML in real time.

CSS Minifier

Compress stylesheets you use to style your HTML preview.

Frequently Asked Questions

How do I open an HTML file online and preview it?: Paste HTML code or load a file into the editor, and the rendered preview updates instantly. This makes quick HTML checks and debugging easy without installing any software.
Can I test external CSS and JavaScript in this HTML viewer?: Yes. Standard external resources can load in the preview when allowed by your browser's security policies, so you can test full styling and scripts alongside your markup.
Is my HTML code sent to a server?: No. All rendering runs entirely in your browser. Your HTML never leaves your device, which keeps private or unfinished markup secure.
Does the preview update automatically as I edit?: Yes. The viewer re-renders the preview pane in real time as you type or paste, so you see changes immediately without clicking a refresh button.
Can I edit HTML and copy it back out?: Yes. Edit your markup directly in the editor pane, then use the toolbar Copy button to grab the finished HTML for your project.