JSON Formatter & Validator

1. Paste your JSON or open a .json file using the Open button
2. Select Beautify to format your JSON with proper indentation and line breaks
3. Select Minify to compress your JSON by removing all whitespace
4. Use the validator to check for syntax errors as you edit
5. Download or copy the formatted JSON when you're done

This JSON formatter runs entirely in your browser, meaning your data never leaves your device. It supports large files, provides automatic error detection with detailed messages, and offers instant formatting without server delays.

The tool is ideal for developers working with APIs, data analysts processing JSON datasets, and anyone who needs to quickly beautify or minify JSON while maintaining complete privacy. Unlike server-based formatters, your sensitive configuration files, API responses, and data structures remain on your device.

Beautify (also called "prettify" or "format") adds indentation, line breaks, and spacing to make JSON human-readable. This is useful when:

• Debugging API responses to understand nested structures
• Reviewing configuration files for errors or inconsistencies
• Sharing JSON with team members for code review
• Learning JSON structure and syntax

Minify (also called "compact" or "compress") removes all unnecessary whitespace to reduce file size. This is useful when:

• Optimizing JSON for production APIs to reduce bandwidth
• Storing JSON in databases or configuration systems where space matters
• Embedding JSON in HTML or JavaScript where size affects page load time

The built-in validator uses JavaScript's native JSON.parse() to detect syntax errors in real-time. Common errors include:

• Missing commas between properties or array elements
• Unclosed quotes, brackets, or braces
• Trailing commas (not allowed in standard JSON)
• Single quotes instead of double quotes for strings
• Unescaped special characters

When an error is detected, the status bar displays the specific error message returned by the parser, helping you quickly identify and fix issues.

Need more text tools? Try the Text Case Converter for quick text transformations or the Base64 Encoder for encoding data.

Is my JSON data uploaded anywhere?

No. All JSON formatting, beautification, minification, and validation happens locally in your browser using JavaScript. Your data never leaves your device and is not uploaded to any server.

Can this tool handle large JSON files?

Yes. The JSON formatter processes files entirely in your browser, so file size limits depend on your device's available memory rather than server restrictions. Files with hundreds of thousands of lines can typically be processed without issues.

Does the validator detect all JSON errors?

Yes. The validator uses JavaScript's native JSON.parse() function to detect syntax errors. It will catch missing commas, unclosed brackets, invalid characters, and other common JSON syntax issues, displaying specific error messages to help you fix problems.