What is toString() in JS?

The toString() method in JavaScript converts objects to string representations, but it differs from JSON.stringify(). Every JavaScript object has toString(), which returns "[object Object]" by default—not useful for data serialization. For arrays, toString() joins elements: [1,2,3].toString() returns "1,2,3". For numbers and booleans, it returns string representations: (123).toString() returns "123". However, toString() does not produce JSON format. To convert objects to JSON strings, use JSON.stringify() instead. ToString() is useful for simple conversions and custom string representations when you override it in your objects. For any data interchange, configuration, or API work, JSON.stringify() is the correct method. Use our JSON Editor at jsonconsole.com/json-editor to work with proper JSON serialization. Understanding the difference between toString() and JSON.stringify() prevents common errors in data handling.