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Overview
Paste minified or poorly indented HTML and get it reformatted with proper nested indentation reflecting the actual DOM structure, powered by js-beautify’s html_beautify. Deeply nested markup that’s hard to scan as a single unbroken line becomes immediately readable, with each element’s children indented one level deeper than their parent so the document’s structure is visible at a glance. This is the counterpart to the HTML Minifier - one strips structure out for production, this one puts readable structure back in for review or debugging. Tag content (including inline scripts and styles) is preserved; only the surrounding whitespace and indentation change. Runs entirely client-side.
Best for: Un-minifying scraped markup to see its structure
How to use this tool
- Paste minified or dense HTML. Scraped page source or a compressed production file.
- js-beautify restructures it. html_beautify rebuilds proper nested indentation reflecting the actual DOM structure.
- Pick a nesting indent. Choose 2 or 4 spaces per nesting level to match how your team writes markup.
- Copy the readable markup. Nesting and structure are now visible for review or debugging.
Can I see how the formatted HTML actually renders, not just how it reads?
This tool only reformats the markup itself - it doesn’t render it. Once the HTML is cleanly indented and easy to scan, paste it into the HTML Viewer to see it rendered live in a sandboxed preview, complete with a responsive width switcher and a console panel for catching any script errors.
Why use this tool
Reveals real DOM structure
Nested indentation shows parent/child relationships that a single unbroken line hides completely.
Powered by html_beautify
Uses js-beautify’s dedicated HTML engine, which understands tag nesting rather than just guessing at it.
Safe on scraped markup
Only whitespace and indentation change - tag content, including inline scripts, stays intact.
Reversible with the HTML Minifier
Strip a page down for production, then bring it back here later to review its structure.
Frequently asked questions
No - this is a beautifier, not a validator or auto-repair tool. It reformats the whitespace and indentation of the HTML you provide, but it doesn’t detect or correct issues like unclosed tags or invalid nesting. If you need to check whether HTML is well-formed, the browser’s DOM parser (used by tools that validate structure) is the right tool for that separate step.
No - only the whitespace between tags and the indentation level change. Since HTML generally collapses insignificant whitespace when rendering, adding readable indentation doesn’t alter layout or behavior; it only makes the source easier for a human to read and navigate.