HTML Formatter
Format HTML instantly in your browser — turn minified or single-line markup into clean, readable, properly indented output.
What Is HTML Formatting?
Browsers don't care about whitespace in HTML — a page's markup can be minified to one dense line by a build tool or a CMS and still render identically. But minified markup is nearly impossible to read: nested divs, spans, and lists all run together with no visual structure.
Formatting adds consistent indentation so the element hierarchy is easy to follow by eye, without changing what the page renders.
Why Format HTML?
Minified HTML is common — production builds strip whitespace to shave page weight, and copying markup from "View Source" or a browser's dev tools often loses its original indentation. When you need to actually read the structure, debug a layout issue, or document a snippet, formatting turns it back into something scannable.
How This Tool Works
This formatter runs entirely in your browser. Paste your HTML into the text area, click Format, and get properly indented output instantly. Your data is never uploaded to any server — formatting happens locally on your device.
Minified vs. Formatted HTML
| Feature | Minified HTML | Formatted HTML |
|---|---|---|
| Layout | Single line, no spaces | Indented, one element per line |
| File size | Smallest | Larger (whitespace adds bytes) |
| Human readability | Hard to scan | Easy to scan and diff |
| Best for | Production page weight | Debugging, code review, documentation |
Keep HTML Minified When
- It's the version actually served to visitors (page weight matters)
- It's embedded inside another minified asset
- It's cached or stored and never read directly
Format HTML When
- You're debugging a layout issue in "View Source" output
- You need to review a template change in a pull request
- You're documenting a markup snippet for other developers
- You're copying HTML out of a browser's dev tools for reuse elsewhere
Common Scenarios for Formatting HTML
Debugging Minified Production Markup
When a live page's HTML is minified, "View Source" returns one dense line. Formatting it first makes it possible to actually locate the element you're trying to debug instead of scrolling sideways forever.
Reviewing a Template Change
Server-rendered templates (Jinja2, Handlebars, ERB output) can end up minified by a build step. Formatting the rendered output before a code review makes the actual structural change visible instead of buried in a single line.
Documenting a Markup Snippet
When writing documentation or a component library entry that includes an HTML example, formatted output is far easier for readers to copy, understand, and adapt than a minified blob.
Cleaning Up Copied Markup
HTML copied from a browser's dev tools, an email client, or a CMS's rich text editor often loses consistent indentation. Running it through a formatter restores a readable structure before you paste it into your own codebase.
Preparing a Bug Report
When reporting a rendering bug, including formatted HTML makes it far easier for someone else to spot the structural issue at a glance. If the same page also needs a printable copy, our HTML to PDF converter turns any page into a PDF directly.
Other Ways to Format HTML
You can also format HTML using your code editor's built-in "Format Document" command (often via the Prettier extension), or Prettier's own command-line tool. FileCast is useful when you don't have either installed.
Frequently Asked Questions
Is it safe to format my markup here?
Yes. This tool processes your markup entirely in your browser. Nothing is uploaded to any server — formatting happens locally on your device. No one else can see or access your data during or after formatting.
Does formatting change what the page renders?
No. Formatting only adds whitespace between tags. Browsers ignore that whitespace when rendering HTML, so the formatted version displays identically to the original.
What indentation does this tool use?
Output is indented with 2 spaces per nesting level.
Does this fix broken or invalid HTML?
No. HTML5 parsing is deliberately lenient — browsers auto-correct issues like an unclosed tag rather than rejecting the page — so there's no "invalid HTML" error to report the way there is for XML or JSON. This tool only re-indents your markup; it doesn't rewrite or auto-correct its structure.
Can I format multiple files at once?
This tool formats one input at a time. Paste your HTML, format it, and copy or download the result. For additional files, clear the input and repeat the process.