🔧 JSON Formatter & Validator

A free, open-source online JSON formatter, validator, and minifier. Runs entirely in your browser — no server, no signup, no data leaves your device.

Live demo: vaultool.com/tools/json-formatter.html

✨ Features

• Beautify — Pretty-print JSON with custom indentation
• Minify — Compress JSON to save space
• Validate — Check JSON syntax with detailed error messages
• Syntax Highlighting — Color-coded keys, strings, numbers, booleans, and null values
• Copy to Clipboard — One-click copy of formatted output
• Load Sample — Built-in sample JSON for quick testing
• Privacy First — 100% client-side, your data never leaves the browser
• Responsive — Works on desktop, tablet, and mobile
• Zero Dependencies — Single HTML file, no build step required

🚀 Quick Start

Just open index.html in any modern browser. No installation needed.

Or try it live at vaultool.com.

🛠️ Tech Stack

• Vanilla HTML/CSS/JavaScript
• Zero dependencies
• No build tools required

📄 License

MIT License — free for personal and commercial use.

🔗 More Free Tools

This is part of the Vaultool free online toolbox — 30+ tools for PDF, image, text processing, and developer utilities.