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JSON Formatter & Validator

Format, beautify, minify, and validate JSON data

Free Online JSON Formatter & Validator

Format, beautify, minify, and validate JSON data instantly with our free online JSON formatter tool. Whether you're a developer debugging API responses, working with configuration files, or analyzing data, our tool makes it easy to transform messy JSON into clean, readable code.

JSON (JavaScript Object Notation) is the standard data format for web applications, APIs, and configuration files. However, minified JSON can be nearly impossible to read. Our formatter adds proper indentation, line breaks, and syntax highlighting to make your JSON data human-readable in seconds.

All processing happens directly in your browser. Your JSON data is never sent to any server, ensuring complete privacy for sensitive information like API keys, credentials, or confidential data structures. Simply paste your JSON, click format, and get instant results.

Features

Format / Beautify

Transform compact JSON into readable, indented format with customizable spacing (2 or 4 spaces).

Minify / Compress

Remove all whitespace to reduce file size, perfect for production use and network optimization.

Validate JSON

Check if your JSON is syntactically correct with clear valid/invalid indicators.

Error Detection

Get detailed error messages with location information to quickly fix syntax issues.

How to Format JSON

1

Paste Your JSON

Copy your JSON data and paste it into the input field. Use "Load Sample" to test with example data.

2

Choose Indentation

Select 2 spaces, 4 spaces, or tab indentation based on your coding style preferences.

3

Click Format or Minify

Use "Format" for readable output or "Minify" for compact, production-ready JSON.

4

Copy the Result

Click the Copy button to copy formatted JSON to your clipboard for use in your projects.

Common Use Cases

API Development

Format and debug API responses to understand data structures and troubleshoot issues.

Configuration Files

Validate and format package.json, tsconfig.json, and other config files for projects.

Data Analysis

Transform raw JSON data exports into readable format for analysis and documentation.

Database Debugging

Format MongoDB documents and NoSQL database records for easier inspection.

Frontend Development

Prepare JSON mock data for testing React, Vue, or Angular applications.

API Documentation

Format JSON examples for API documentation with proper indentation and structure.

Frequently Asked Questions

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data interchange format that is easy for humans to read and write, and easy for machines to parse and generate. It is widely used for API responses, configuration files, and data storage.

Why format JSON?

Formatted JSON with proper indentation is much easier to read, debug, and understand. Minified JSON (single line, no spaces) is hard to comprehend but better for production use as it reduces file size and transfer time.

What makes JSON invalid?

Common JSON errors include: missing commas between elements, trailing commas after the last element, single quotes instead of double quotes, unquoted keys, and undefined/NaN values. Our validator shows exactly where errors occur.

Is my data secure?

Yes. All JSON processing happens locally in your browser using JavaScript. Your data never leaves your computer or gets sent to any server. This makes it safe to use with sensitive or confidential data.

What is the difference between format and minify?

Format adds indentation and line breaks to make JSON readable. Minify removes all unnecessary whitespace to reduce file size. Use format for development and debugging, minify for production and network transfer.

Can I format large JSON files?

Yes, our tool can handle large JSON files. However, extremely large files (10MB+) may cause browser slowdowns. For massive datasets, consider using command-line tools like jq or dedicated JSON processing software.