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JSON Data Types


Valid Data Types

In JSON, values must be one of the following data types:

  • a string
  • a number
  • an object (JSON object)
  • an array
  • a boolean
  • null

JSON values cannot be one of the following data types:

  • a function
  • a date
  • undefined

JSON Strings

Strings in JSON must be written in double quotes.

Example

{ "name":"John" }

JSON Numbers

Numbers in JSON must be an integer or a floating point.

Example

{ "age":30 }

JSON Objects

Values in JSON can be objects.

Example

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

Objects as values in JSON must follow the same rules as JSON objects.



JSON Arrays

Values in JSON can be arrays.

Example

{
"employees":[ "John", "Anna", "Peter" ]
}

JSON Booleans

Values in JSON can be true/false.

Example

{ "sale":true }

JSON null

Values in JSON can be null.

Example

{ "middlename":null }