Code Formatter
Free, browser-based tools to format, beautify, minify, and validate code. Nothing is uploaded to a server — everything runs locally in your browser.
Available tools
CSS Formatter
Format, beautify, and minify CSS instantly in your browser.
HTML Formatter
Format, beautify, and minify HTML instantly in your browser.
JavaScript Formatter
Format, beautify, and compress JavaScript instantly in your browser.
JSON Formatter
Format, validate, and beautify JSON instantly in your browser.
JSON Tree Viewer
Browse pasted JSON as an interactive, expandable tree instead of a flat text block.
About this code formatter
Every tool on this page follows the same idea: take code that's minified, inconsistently indented, or just messy, and turn it into something a human can actually scan — consistent indentation, one statement or declaration per line, and a structure that matches the code's real nesting. No configuration to fight with, no accounts, no uploads: paste your code in and the result updates instantly.
Right now that covers JSON, CSS,HTML, and JavaScript — each with its own dedicated formatter and minifier above — plus a JSON Tree Viewer for exploring a JSON document's structure rather than reformatting it as text. More languages are planned as this toolset grows. Every one of them runs directly in your browser, so your code never leaves your device.
One honest caveat: the formatters expect reasonably well-formed input. If you paste in code with mismatched braces, unclosed tags, or otherwise broken syntax, the output can end up looking wrong in places — there's only so much a formatter can infer from invalid source. Fix the underlying syntax first for the best result.
Frequently asked questions
- What is a code formatter / code beautifier?
- A code formatter (also called a beautifier or pretty-printer) rewrites code with consistent indentation and line breaks without changing what it does — turning a dense, hard-to-read block into something a human can actually scan.
- Is it safe to format code online?
- It depends entirely on where the processing happens. Every formatter on this page runs the formatting logic in your own browser using JavaScript — your code is never uploaded to a server, so it's safe to paste in code you wouldn't want to send anywhere, including real API keys or proprietary snippets.
- What's the difference between formatting and minifying code?
- Formatting (Pretty mode) adds whitespace and line breaks for readability. Minifying does the opposite — it strips comments and unnecessary whitespace to produce the smallest possible file size for production, while keeping the code functionally identical.
- Will minifying my code break it or change how it behaves?
- It shouldn't, for well-formed input. Each minifier here is careful to leave string contents, template literals, and (for JavaScript) regex literals untouched, and only removes whitespace/comments it's certain are safe to remove. See each tool's own limitations section for the specific edge cases its approach can't guarantee.
- Which languages can I format here?
- JSON, CSS, HTML, and JavaScript today, each with its own dedicated formatter/minifier — plus a JSON Tree Viewer for exploring JSON structure rather than reformatting it as text. More languages are planned as this toolset grows.