JSON Formatter & Validator - Free Online Tool
Format, validate, and prettify JSON data instantly. Syntax highlighting and error detection included.
Input JSON
Formatted JSON
How to use the JSON Formatter:
🎨 Format & Prettify
Makes your JSON readable with proper indentation and line breaks. Perfect for debugging and reviewing JSON data.
🗜️ Minify
Removes all unnecessary whitespace to reduce file size. Ideal for production environments and API responses.
✅ Validate
Checks your JSON syntax for errors and provides detailed error messages with line numbers for easy debugging.
📁 Code Folding
Collapse and expand JSON sections (objects and arrays) directly in the code view. Click the +/- buttons to fold sections with previews.
Key Features
- Readable formatting with indentation and syntax highlighting
- Instant JSON validation with precise error location
- Pretty print and minify modes for development and production
- Tree view and code view for easy navigation of large payloads
- Copy, download, and fullscreen workspace for productivity
- Works entirely in your browser—no data is stored
How to Use
- Paste or drop your JSON into the input area.
- Click Format to prettify and validate. Errors are highlighted with line and column.
- Toggle between Tree and Code views to explore nested objects.
- Use Minify to compress the output for APIs, logs, or storage.
- Copy or download the result for your project or documentation.
Common Use Cases
Developers, analysts, QA engineers, and data enthusiasts use our formatter to quickly debug API responses, tidy configuration files, prepare documentation examples, and validate webhook payloads. The tool supports very large JSON and is optimized for performance.
How It Works
JSON formatting improves readability by adding proper indentation and line breaks while validating syntax. Our tool processes JSON entirely in your browser using native JavaScript parsing.
Step-by-Step Process:
- Paste or type your JSON data into the input editor
- The tool automatically validates syntax and highlights errors
- Choose between pretty-print formatting or minification
- Copy the formatted result or download as a .json file
Use Cases
JSON formatting is essential for developers, data analysts, and anyone working with APIs, configuration files, or structured data.
API Development & Debugging
Format API responses, debug webhook payloads, and validate JSON data structures during development and testing.
Configuration Management
Clean up configuration files, validate settings, and prepare readable JSON for documentation and deployment.
Data Analysis & Processing
Format large datasets, validate data integrity, and prepare JSON for import into analysis tools and databases.
Documentation & Sharing
Create readable examples for documentation, tutorials, and code sharing with proper formatting and validation.
Privacy Promise
JSON data often contains sensitive information like API keys, user data, and business logic. Our formatter ensures complete privacy protection.
🔒 Your data never leaves your browser - 100% client-side processing guaranteed
Frequently Asked Questions
What is a JSON formatter and why do I need it?
A JSON formatter improves readability by adding proper indentation and line breaks to compressed JSON. It also validates syntax and helps identify errors, making JSON easier to read and debug.
Is my JSON data stored or transmitted anywhere?
No. All formatting and validation happens locally in your browser using native JavaScript. Your JSON data never leaves your device and is not stored on our servers.
Can the tool handle large JSON files?
Yes. Our formatter is optimized for performance and can handle very large JSON files. Processing is done efficiently in your browser without size limitations.
What's the difference between pretty print and minify?
Pretty print adds indentation and line breaks for readability. Minify removes all unnecessary whitespace to reduce file size for production use or transmission.
How does error detection work?
The validator uses native JSON parsing to detect syntax errors and highlights the exact location with line and column numbers, making it easy to identify and fix issues quickly.