JSON Formatter

What is JSON?

JSON (JavaScript Object Notation) is a text-based format for representing structured data. It's the standard data format used by REST APIs, configuration files, databases like MongoDB, and countless other systems. A valid JSON document consists of key-value pairs enclosed in curly braces (for objects) or ordered values in square brackets (for arrays).

How to Use This JSON Formatter

1. Paste or type your JSON into the input box on the left.
2. The formatter validates and formats your JSON automatically.
3. Copy the formatted output or download it as a .json file.
4. Use the indent selector to choose 2-space, 4-space, or tab indentation.

Common JSON Errors and How to Fix Them

• Trailing comma — Remove the comma after the last item in an array or object.
• Single quotes — JSON requires double quotes. Replace 'key' with "key".
• Undefined or comments — JSON does not support JavaScript values like undefined or // comments.
• Unescaped characters — Special characters inside strings must be escaped (e.g. \n, ").

Valid JSON Example

{
  "name": "Alice",
  "age": 30,
  "email": "alice@example.com",
  "address": {
    "city": "New York",
    "country": "USA"
  },
  "tags": ["developer", "designer"]
}