JSON.stringify()
Converts a JavaScript value to a JSON string.
Syntax
JSON.stringify(value, replacer, space)Parameters
| Name | Type | Required | Description |
|---|---|---|---|
value | any | Yes | The value to convert to a JSON string. |
replacer | Function | Array | No | A function (key, value) to transform values, or an array of keys to include. |
space | string | number | No | Indentation: a number of spaces (max 10) or a string used for pretty-printing. |
Returns
string | undefined — The JSON string, or undefined if the value is a function or undefined.
Throws
TypeError— the value contains a circular reference or a BigInt.
Examples
console.log(JSON.stringify({ a: 1, b: [2, 3] }));
Output
{"a":1,"b":[2,3]}
console.log(JSON.stringify({ a: 1 }, null, 2));
Output
{
"a": 1
}
Notes
undefined, functions, and symbols are omitted from objects and become null in
arrays. Throws on circular references and BigInt. A `toJSON()` method on a
value customizes its serialization (e.g. Date returns an ISO string).
Browser & runtime support
| Environment | Since version |
|---|---|
| chrome | 4 |
| firefox | 3.5 |
| safari | 4 |
| edge | 12 |
| node | 0.10 |