What is JSON.stringify()?
JSON.stringify() is a built-in JavaScript method that converts JavaScript objects, arrays, or values into JSON (JavaScript Object Notation) strings. This is essential for:
- Sending data to web servers via HTTP requests
- Storing data in localStorage or sessionStorage
- Converting objects to strings for transmission
- Creating JSON files from JavaScript data
Use our free JSON Beautifier to format the stringified output, or our JSON Fixer to repair any issues.
Syntax
JSON.stringify(value, replacer, space)value
The JavaScript object, array, or value to convert to JSON string
replacer (optional)
A function or array to transform values before stringifying
space (optional)
Number of spaces for indentation (0-10) for pretty printing
Examples
Simple Object:
const obj = { name: "John", age: 30 };
JSON.stringify(obj);
// Output: '{"name":"John","age":30}'With Pretty Print (spaces = 2):
JSON.stringify(obj, null, 2);
// Output:
// {
// "name": "John",
// "age": 30
// }More JSON Tools
Need to parse JSON strings? Use our JSON Beautifier or JSON Fixer for validation and repair.