JSON formatter
Format and validate JSON instantly. Better than VS Code extensions—no install, works anywhere. Syntax highlighting included.
A JSON formatter helps you format, validate, and minify JSON data for readability, debugging, and optimization. This tool is essential for developers working with APIs, frontend developers handling JSON responses, backend developers debugging data structures, and anyone who needs to work with JSON data. By formatting JSON, you can improve code readability, identify syntax errors, validate data structures, and optimize JSON for transmission. The tool processes JSON entirely in your browser, ensuring privacy and instant formatting without any server transmission.
What is JSON formatter?
JSON (JavaScript Object Notation) is a lightweight data interchange format used for transmitting and storing structured data. A JSON formatter takes compact or minified JSON and reformats it with proper indentation and line breaks for human readability. The formatter also validates JSON syntax, checking for errors like missing quotes, trailing commas, or invalid characters. Additionally, the tool can minify JSON by removing whitespace to reduce file size. JSON formatting is essential for debugging, code review, documentation, and understanding complex data structures. All processing happens client-side in your browser.
Common use cases
- API development: Format JSON responses from APIs for debugging and understanding data structures
- Code debugging: Format minified JSON from production systems to identify issues or understand data flow
- Data validation: Validate JSON syntax before using it in applications or storing it in databases
- Documentation: Format JSON examples in documentation for better readability and understanding
- Configuration files: Format JSON configuration files for easier editing and maintenance
- Data optimization: Minify JSON for production use to reduce file size and improve transmission speed
Limitations and common mistakes
- Invalid JSON cannot be formatted. The tool will display error messages, but you must fix syntax errors manually
- Very large JSON files (over 10MB) may experience processing delays or browser performance issues
- The formatter does not validate JSON schema or data types—it only checks syntax validity
- Complex nested structures with deep nesting may be difficult to read even when formatted
- The tool does not preserve comments, as JSON standard does not support comments
How to use this json formatter
- Paste or type your JSON into the input field
- The JSON will be automatically formatted when you click away from the input or manually trigger formatting
- Adjust indentation using the slider (2 or 4 spaces) to match your coding style preferences
- Use "Validate" button to check if JSON is valid and see any error messages
- Use "Minify" button to compress JSON by removing all whitespace for production use
- Copy the formatted JSON using the copy button
Related Tools
Frequently Asked Questions
Is invalid JSON supported?
No, invalid JSON cannot be formatted. The tool will display the exact error message to help you identify and fix syntax issues like missing quotes, trailing commas, or invalid characters.
Does formatting change data?
No, formatting only changes whitespace and indentation. The actual data structure, values, and content remain exactly the same. Formatted JSON is functionally identical to the original.
How does JSON formatting work?
The formatter parses your JSON and reformats it with proper indentation and line breaks. All processing happens in your browser - your data never leaves your device, ensuring complete privacy.
Can I customize the indentation?
Yes, you can choose between 2 or 4 spaces for indentation using the slider. The default is 2 spaces, which is a common standard in many coding style guides.
What is JSON minification?
Minification removes all whitespace, line breaks, and unnecessary formatting to create the smallest possible JSON file. This is useful for production environments where file size matters.
Is my JSON data secure?
Yes, all processing happens entirely in your browser. Your JSON data is never sent to any server, stored anywhere, or transmitted over the network, ensuring complete privacy and security.