Json Format

JSON Formatter

Format and validate JSON — pretty-print with configurable indentation or minify to a single line.

Input

Output

Instructions

1. Receive the raw JSON string from the user. 2. Determine the requested action (default: format). 3. Attempt to parse the JSON: - Call JSON.parse(input) conceptually — parse the string strictly following JSON spec. - If parsing fails, report the error with as much detail as possible (e.g., "Unexpected token at position 42", "Missing closing bracket"). 4. For format action: - Serialize the parsed value back to a string with the requested indent size (default: 2 spaces). - Use JSON.stringify(parsed, null, indentSize) semantics: keys are sorted by insertion order (not alphabetically), arrays and objects are expanded across multiple lines, strings are double-quoted. 5. For minify action: - Serialize with no indentation or extra whitespace: JSON.stringify(parsed) semantics. 6. For validate action: - If parsing succeeded, report "Valid JSON" along with type and top-level key count if it is an object. - If parsing failed, report the error message. 7. If sort-keys option is requested, sort all object keys alphabetically at every nesting level before serializing. 8. Output the result.

Options

Examples

Format (default, 2-space indent)

Input:

{"name":"Alice","age":30,"hobbies":["reading","coding"]}

Output:

{
  "name": "Alice",
  "age": 30,
  "hobbies": [
    "reading",
    "coding"
  ]
}

Minify

Input:

{
  "name": "Alice",
  "age": 30
}

Output:

{"name":"Alice","age":30}

Validate — invalid JSON

Input:

{name: 'Alice', age: 30}

Output:

Invalid JSON: Unexpected token 'n' at position 1. Keys must be double-quoted strings and string values must use double quotes, not single quotes.

Format with 4-space indent and sort-keys

Input:

{"z":3,"a":1,"m":2}

Output:

{
    "a": 1,
    "m": 2,
    "z": 3
}

Error Handling

Format (default, 2-space indent)

Input:

{"name":"Alice","age":30,"hobbies":["reading","coding"]}

Output:

{
  "name": "Alice",
  "age": 30,
  "hobbies": [
    "reading",
    "coding"
  ]
}

Minify

Input:

{
  "name": "Alice",
  "age": 30
}

Output:

{"name":"Alice","age":30}

Validate — invalid JSON

Input:

{name: 'Alice', age: 30}

Output:

Invalid JSON: Unexpected token 'n' at position 1. Keys must be double-quoted strings and string values must use double quotes, not single quotes.

Format with 4-space indent and sort-keys

Input:

{"z":3,"a":1,"m":2}

Output:

{
    "a": 1,
    "m": 2,
    "z": 3
}