Code Beautifier
CodeBeautify HTML, CSS, or JavaScript with consistent indentation and structure. Rule-based, runs entirely in your browser — your code is never uploaded anywhere.
What is a Beautifier?
The Code Beautifier formats HTML, CSS, and JavaScript source code with consistent indentation and one statement (or declaration, or element) per line, making the code's logical structure immediately visible. It is the essential step between receiving compact, minified, or poorly indented code and editing it as a human.
Code arrives in unreadable form from many sources: minified production assets, generated markup from a CMS, output from a templating engine, or a snippet pasted from a chat message. A single-line HTML page that runs all elements together with no whitespace is valid HTML that the browser renders perfectly — but it is nearly impossible to read, edit, or debug:
<html><head><title>Hello</title></head><body><div class="container"><h1>Welcome</h1><p>This is a paragraph.</p></div></body></html>
The Code Beautifier turns this into a structured document where every element opens on its own line, children are indented, and the nesting hierarchy is immediately visible from the indentation alone.
The formatter uses a rule-based approach for each language rather than a full grammar parser. This keeps it fast, dependency-free, and safe for any input — malformed code that would crash a parser is handled gracefully. The trade-off is that complex edge cases (deeply nested ternaries in JavaScript, CSS variables inside calc expressions, or multi-level HTML attribute values) may not be formatted perfectly, but the result is always valid and usable.
All processing runs entirely in your browser. No code you paste is ever sent to a server or stored. Use the Code Minifier to compress back to production format after editing, or the CSS Formatter for a CSS-specific formatter with property sorting. The JSON Formatter handles JSON objects inside JavaScript.
How to use this Beautifier calculator
- Paste your code into the Code input box — this can be minified, single-line, or inconsistently indented source in HTML, CSS, or JavaScript.
- Select the correct Language from the dropdown: HTML, CSS, or JavaScript.
- Choose an Indent Size: 2 spaces (default) or 4 spaces.
- The Formatted Code output updates instantly as you change any option.
- Click Copy to copy the beautified code to your clipboard.
Formula & Methodology
Each language uses a different structural strategy: HTML: The input is split into tag tokens (<tag attrs>,</tag>, self-closing<tag />) and text nodes. Block-level elements (div, section, p, h1–h6, ul, li, etc.) are placed on their own line and increase the current indent depth for their children. Void elements (br, img, input) are placed on their own line but do not increase depth. Inline elements (span, a, em, strong) are kept attached to their surrounding text to preserve readable inline structure. CSS: Block comments are stripped. The source is scanned character by character for{and}. Everything before{is the selector (printed on its own line); everything between{and}is split on;and printed as individual indented declarations. JavaScript: A character-by-character scan tracks string literals (single, double, template), line comments (//), and block comments (/* */) to avoid treating their contents as structural. Outside those,{closes the current statement and opens a new indented block;}closes the block and moves back one indent level;;ends a statement and starts a new indented line. Before (HTML):html <html><head><title>Hello</title></head><body><div class="container"><h1>Welcome</h1><p>This is a paragraph.</p></div></body></html>After (2 spaces):html <html> <head> <title>Hello</title> </head> <body> <div class="container"> <h1>Welcome</h1> <p>This is a paragraph.</p> </div> </body> </html>