Client-Side UtilityLocal memory execution • Zero server telemetry
HTML, CSS & JavaScript Code Formatter (Beautifier)
Format and beautify unindented or minified HTML, CSS, and JavaScript source code. Configurable 2-space, 4-space, or tab indentation with client-side syntax diagnostics.
DMaintained by Developer Tools Desk
Published
Indentation Style:
0 lines • 0 chars
Formatted HTML Output
Awaiting CodePaste or type code on the left to generate formatted, indented source code.
DMaintained by Developer Tools Desk
Published
Calculation Methodology & Formula
Tokenizes lexical source code into hierarchical AST elements and re-serializes with standardized block indenting, void tag rules, and declaration alignment.
Input Tokens -> Structural Indentation -> Standardized OutputWorked Example: Minified HTML Document Beautification
Single-line minified markup transformed into an indented DOM hierarchy.
language:HTML
code Snippet:<div class="card"><h1>Title</h1><p>Text</p></div>
Expected OutputMulti-line indented HTML with proper nested child element tags
Detects container boundaries and spaces children by configurable indent levels.
Technical Constraints & Limitations
- Does not execute user JavaScript; syntax validation parses code structure without runtime evaluation.
- JSX, TypeScript-specific syntax, or experimental TC39 proposals should be pre-compiled to standard ECMAScript.
Frequently Asked Questions
Is my source code sent to an external server?
No. All formatting runs 100% locally inside your browser memory using client-side tokenizers. Your code never leaves your device.
Which indentation option is standard?
Modern web projects predominantly use 2 spaces for HTML, CSS, and JavaScript. Python and some backend systems prefer 4 spaces.