The HTML Previewer is a free online tool that lets you paste raw HTML code and instantly see how it renders in a browser. Whether you are building an email template, debugging a blog post, testing AI-generated markup, or learning HTML basics, this tool gives you a live visual preview without needing to save files or open a code editor.
How it works: Paste or type HTML into the input area, and the rendered output appears instantly in the preview pane below. The preview is sandboxed for security — scripts will not execute, keeping your browser safe while you experiment with any markup.
Built-in tools: Use the Prettify button to auto-format messy or minified HTML into readable, indented code. The Copy button puts your HTML on the clipboard with one click. The responsive toggle lets you preview your HTML at desktop (full width), tablet (768px), and mobile (375px) breakpoints — essential for testing email templates and responsive layouts.
Stats at a glance: A live stats bar shows character count, word count (visible text only, tags excluded), line count, and HTML element count — useful for checking email template size limits or content length.
No signup required, no data sent to any server. Your HTML stays entirely in your browser.
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How to Use the HTML Previewer
1. Paste your HTML into the input area at the top of the page 2. See the live preview appear instantly below 3. Prettify your code with one click to add proper indentation 4. Test responsive layouts by toggling between Desktop, Tablet, and Mobile preview widths 5. Copy your formatted HTML to the clipboard when ready
Common Uses
- Preview email templates before sending - Test AI-generated HTML output - Debug blog post formatting - Learn HTML by seeing changes in real time - Check responsive layout breakpoints - Validate HTML structure visually
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