JSON Cheat Sheet

{
  "name": "Workshelve",
  "active": true
}

JSON objects use curly braces with quoted string keys.

[
  "json",
  "yaml",
  "xml"
]

JSON arrays use square brackets and comma-separated values.

{
  "tool": {
    "id": "json-parser",
    "tags": ["format", "data"]
  }
}

Objects and arrays can be nested freely as long as syntax stays valid.

{
  "title": "Hello world"
}

Strings must use double quotes in JSON.

{
  "count": 25,
  "ratio": 0.75
}

JSON numbers do not use quotes unless you want them treated as strings.

{
  "enabled": true,
  "archived": false
}

Boolean values are lowercase true and false.

{
  "owner": null
}

Use null for an intentionally empty value.

{
  "message": "Line 1\nLine 2\tTabbed"
}

Use backslash escapes inside JSON strings for control characters.

JSON.stringify(value, null, 2)

This produces readable indented JSON in JavaScript.

JSON.parse(text)

Parsing turns JSON text into a JavaScript value and throws on invalid syntax.

[{"id":1},{"id":2}]

A JSON document can be an array, not only an object.

{
  "note": "JSON does not allow comments"
}

Standard JSON does not support comments, trailing commas, or single-quoted strings.