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Input

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Output

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{
  "name": "BigDevSoon",
  "version": "2.0.0",
  "description": "Learn frontend development through real-world projects",
  "features": [
    "projects",
    "challenges",
    "practice-problems"
  ],
  "config": {
    "theme": "dark",
    "language": "en",
    "notifications": true
  },
  "stats": {
    "users": 15000,
    "projects": 80,
    "challenges": 100
  }
}

JSON Formatter

Data

Format, validate, and minify JSON data with line numbers. Real-time validation as you type.

What is JSON formatting?

JSON (JavaScript Object Notation) is the most widely used data interchange format on the web. APIs, configuration files, and databases all rely on JSON to transmit structured data. Properly formatted JSON uses consistent indentation and line breaks so you can quickly scan nested objects and arrays, spot missing commas or brackets, and understand the shape of an API response at a glance.

When to use this tool

Use the JSON Formatter whenever you receive minified API responses, need to validate a JSON payload before sending it to an endpoint, or want to compress JSON for production use. It handles common issues like trailing commas, single quotes instead of double quotes, and duplicate keys. It works entirely in your browser — no data is sent to any server.

How developers use JSON daily

Frontend developers work with JSON in fetch responses, localStorage, and configuration files like package.json and tsconfig.json. Backend developers parse JSON request bodies, serialize database records, and define API schemas. Having a quick, reliable formatter saves time when debugging network requests in DevTools or preparing test fixtures for unit tests.

Frequently Asked Questions

Is this JSON formatter free to use?

Yes, completely free with no sign-up required. All processing happens in your browser — no data is sent to any server.

Does this tool validate JSON automatically?

Yes. Validation happens in real time as you type. A green banner confirms valid JSON, while an error banner pinpoints syntax issues with line and column detail — no button clicks needed.

What is the difference between formatting and minifying JSON?

Formatting adds indentation and line breaks to make JSON human-readable. Minifying removes all whitespace to reduce file size, which is useful for production API payloads and configuration files. Both modes include line numbers for easy reference.

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