✨ JSON Formatter & Validator
🌳 Tree View
Visual representation of your JSON structure
🧪 Example JSON
Click an example to load it into the formatter
📚 Understanding JSON
JSON (JavaScript Object Notation) is a lightweight data interchange format that's easy for humans to read and write and easy for machines to parse and generate. It's the most common format for API communication and configuration files.
Key Features:
- Data Types - Supports strings, numbers, booleans, null, objects and arrays
- Lightweight - Minimal syntax and small file sizes
- Language Independent - Supported by virtually every programming language
- Human Readable - Easy to read and edit when properly formatted
- Self-Describing - Structure and data are combined in one format
Common Use Cases:
- REST APIs - Standard format for API requests and responses
- Configuration Files - package.json, tsconfig.json, settings files
- Data Storage - NoSQL databases like MongoDB use JSON-like documents
- Web Development - AJAX calls, localStorage and state management
- Data Exchange - Transferring data between different systems and languages
Best Practices:
- Always validate JSON before deploying to production
- Use consistent indentation (2 or 4 spaces)
- Avoid trailing commas (not valid in JSON)
- Use double quotes for strings, not single quotes
- Minify JSON for production to reduce file size
- Format JSON for development and debugging
Relaxed JSON Support:
This tool accepts relaxed JSON syntax commonly used in JavaScript, Ruby and PHP:
- Unquoted keys: Input:
{name: "John", age: 30}→ Output:{"name": "John", "age": 30} - Arrow syntax: Input:
{name => "John", count => 5}→ Output:{"name": "John", "count": 5} - Mixed syntax: Combine both styles freely, the formatter will normalize everything
❓ Frequently Asked Questions
A JSON formatter (also called JSON beautifier or pretty printer) transforms compact, hard-to-read JSON into a clean, indented format with proper spacing. You need it to read API responses, debug JSON data, validate syntax, find errors quickly and make configuration files human-readable. Our tool also validates JSON and highlights syntax errors.
Paste your JSON into the input area and click 'Format & Validate'. The tool will automatically check for syntax errors, missing brackets, invalid characters, trailing commas and other issues. If errors are found, you'll see detailed error messages with line and column numbers to fix the problem quickly.
Formatting (beautifying) adds indentation, line breaks and spacing to make JSON human-readable. Minifying removes all whitespace and line breaks to create the smallest possible file size for production use, reducing bandwidth and improving API performance. Use formatting for development and debugging, minification for production.
Absolutely! All JSON formatting, validation and minification happens locally in your browser using JavaScript. No data is ever transmitted to our servers or any third party. You can use this tool completely offline. Your API keys, sensitive data and configuration files remain 100% private.
Yes! Our JSON formatter can handle large files, limited only by your browser's memory. For very large files (>10MB), processing may take a moment, but the tool will handle it efficiently. The formatter works well with deeply nested JSON objects and large arrays.
The validator detects: syntax errors, missing or extra brackets/braces, unclosed strings, trailing commas, invalid characters, incorrect value types, malformed objects and arrays, duplicate keys and Unicode issues. Each error shows the exact line and column number for quick fixing.