Formula
tokenise → build a tree of tags → print block elements on their own lines, inline content together
- Void elements (br, img, input…) and raw-text elements (script, style, pre, textarea) are handled specially.
Only the whitespace between tags changes.
Worked example
Minified snippet
- HTML
- <div><p>Hello <b>world</b>!</p><ul><li>One<li>Two</ul></div>
- Indent
- 2 spaces
Result
Formatted — see below
Lines: 7
Size: 90 bytes
<div>
<p>Hello <b>world</b>!</p>
<ul>
<li>One</li>
<li>Two</li>
</ul>
</div>How it works
Each block-level element goes on its own line, indented by its depth in the tree; inline elements such as <b>, <a> and <span> stay inside their paragraph so text still reads naturally. Attributes are kept exactly as written, including quoted values that contain >.
Whitespace inside <pre> and <textarea>, and the contents of <script> and <style>, is preserved, because changing it could change how the page behaves. Optional closing tags such as </li> and </td> are understood. The formatter points out unclosed or unmatched tags but isn't a validator. For the CSS inside a page use the CSS Formatter; for data use the JSON Formatter.
Assumptions and limits
- Collapses runs of spaces in normal text to one space, as browsers render them.
- Input limited to 1 MB.
Related tools
CSS FormatterFormat CSS with consistent indentation, or minify it, with errors that give the line number.JSON FormatterPretty-print JSON with 2 or 4 spaces or tabs and optional key sorting — numbers are never altered.Color ConverterConvert colours between HEX, RGB, HSL and HSV, with WCAG contrast ratios against white and black.URL Encode and DecodePercent-encode or decode URLs and query values — as a component, a full URL or form data.Word CounterCount words, characters, sentences and paragraphs, with reading time and the most-used words.HTML Entity Encoder and DecoderEscape text for HTML or decode entities like & and © back to characters.Markdown PreviewerPreview Markdown as you type and copy the HTML it produces, safely, in your browser.