Free JSON Formatter & Validator Online
Format and validate JSON data instantly with our free online JSON formatter. Transform messy, unreadable JSON into clean, properly indented structure with syntax highlighting. Validate JSON syntax to catch errors, minify for production, and export formatted results. Perfect for developers, API testing, data analysis, and debugging JSON responses from REST APIs.
Key Features
Instant Formatting: Beautify JSON with one click. Automatically adds proper indentation, line breaks, and spacing to make complex JSON data structures easy to read and understand. Choose between 2 spaces, 4 spaces, or tab indentation.
Validation & Error Detection: Real-time JSON validation shows exactly where syntax errors occur. Get detailed error messages pointing to the specific line and character causing issues, making debugging fast and simple.
Minify for Production: Compress formatted JSON by removing all unnecessary whitespace and line breaks. Reduce file size for API responses and data transfer while maintaining valid JSON structure.
Syntax Highlighting: Color-coded JSON elements make it easy to distinguish between keys, values, strings, numbers, booleans, and null values. Visual structure helps identify data types at a glance.
How to Use
- Input JSON: Paste JSON data directly or upload a .json file from your computer
- Format: Click "Format JSON" to beautify with proper indentation and structure
- Validate: Use "Validate" button to check syntax and catch errors instantly
- Customize: Choose indentation style - 2 spaces, 4 spaces, or tabs
- Minify: Click "Minify JSON" to compress for production use if needed
- Export: Copy to clipboard or download as .json file for your project
Common Use Cases
API Development: Format API responses from REST endpoints to inspect data structure. Validate request/response payloads before sending to ensure proper JSON syntax. Debug API integration issues by viewing formatted JSON clearly.
Data Analysis: Parse and examine large JSON datasets from databases or file exports. Format complex nested objects to understand data relationships and hierarchy. Validate JSON exports before importing to other systems.
Configuration Files: Format config.json files for applications to improve readability. Validate configuration syntax before deployment to catch errors early. Maintain consistent JSON formatting across team projects.
JSON Validation
The validator checks for common JSON errors including missing commas, unclosed brackets, unquoted keys, trailing commas, and invalid escape sequences. Error messages show the exact location of issues with line and column numbers. Validate before using JSON in production to prevent runtime errors.
Best Practices
Always validate JSON before using it in applications or APIs. Use formatted JSON during development for easier debugging and code reviews. Minify JSON for production to reduce file size and improve load times. Choose consistent indentation style across your project - 2 spaces is industry standard. Remove sensitive data before formatting JSON from production systems. Use JSON formatter to verify API responses match expected structure during integration testing.
Formatting Standards
Properly formatted JSON uses consistent indentation for nested objects and arrays. Keys are always strings in double quotes. String values use double quotes, not single quotes. No trailing commas after last array or object element. Boolean values are lowercase (true/false). Use null for empty values, not undefined.