Format, Minify & Validate JSON Instantly

JSON Formatter is a powerful, privacy-first tool that helps developers work with JSON data effortlessly. Beautify messy API responses, minify for production, or validate with detailed error messages—all without your data ever leaving your browser.

One-Click Formatting

Transform minified JSON into perfectly indented, readable code:

• 2, 3, or 4 space indentation options
• Syntax highlighting with proper color coding
• Line numbers for easy reference
• Instant results with no server roundtrips

Privacy First

Unlike many online JSON tools, we never send your data anywhere:

• 100% browser-based processing
• No data logging or analytics on content
• Safe for sensitive data like API keys and PII
• Works offline once loaded

Powerful Editor

Powered by Monaco Editor—the same engine behind VS Code:

• Full syntax highlighting for JSON
• Error highlighting with line markers
• Keyboard shortcuts for power users
• Search and replace functionality
• Auto-bracket matching

Detailed Validation

When your JSON is invalid, get precise error messages:

• Line and column numbers pointing to the error
• Clear error descriptions explaining the issue
• Visual markers in the editor
• Quick fixes with helpful suggestions

File Operations

Work with JSON files seamlessly:

• Upload JSON files directly
• Download formatted or minified output
• Copy to clipboard with one click
• Load sample to test features

Stats at a Glance

See useful metrics about your JSON:

• Character count
• Line count
• Validity status
• Minification savings

Developer-Friendly Stack

Built with modern tools:

• Next.js 15 with App Router
• TypeScript for type safety
• Monaco Editor for code editing
• shadcn/ui + Framer Motion for UI
• Tailwind CSS for styling
• PWA support for offline use

Use Cases

Perfect for:

• Debugging API responses - Format and inspect JSON payloads
• Config file management - Validate before deploying
• Data preparation - Minify for production use
• Code reviews - Format consistently for clean diffs
• Learning - Explore JSON structure with syntax highlighting