What does formatting change?

It parses JSON and rewrites it with consistent indentation and spacing, making nested data easier to read without changing its values.

Can it find syntax errors?

Yes. Invalid JSON is rejected with an error so you can locate issues such as missing quotes, commas, or closing brackets.

Is the JSON uploaded?

No. Formatting and validation happen entirely in your browser.

JSON Formatter

Format, validate, and analyze JSON with professional tools and insights.

Input & Settings

JSON Input

Quick Start

Format Mode

Auto-format on type

Show line numbers

JSON Formatting Examples

Unformatted Input

{"name":"John","age":30,"city":"New York"}

Pretty Output

{
  "name": "John",
  "age": 30,
  "city": "New York"
}

Additional Examples

Formatting Minified JSON

Input:
{"name":"Alice","age":30,"city":"New York"}

Output:
{
  "name": "Alice",
  "age": 30,
  "city": "New York"
}

Converts a compact, single-line JSON string into a human-readable format with indentation.

Validating and Formatting Complex JSON

Input:
[ { "id": 1, "items": [ "apple", "banana" ] }, { "id": 2, "active": true, "config": null } ]

Output:
[
  {
    "id": 1,
    "items": [
      "apple",
      "banana"
    ]
  },
  {
    "id": 2,
    "active": true,
    "config": null
  }
]

Formats nested arrays and objects with consistent indentation, handling different data types (number, string, boolean, null).

Detecting Syntax Errors

Input:
{
  "name": "Bob",
  "age": 40 // Missing comma
  "isStudent": false
}

The tool will identify the missing comma after the 'age' field and report a validation error.

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