JSON.stringify vs JSON.parse in JavaScript (with thumb rule)

JSON (JavaScript Object Notation) is a lightweight data interchange format that is easy to read and write. It's commonly used to send data from a server to a web page and vice versa.

Two important methods for working with JSON in JavaScript are JSON.stringify() and JSON.parse(). In this article, we'll discuss the differences between these two methods and when to use each one in frontend and backend development.

JSON.stringify()

The JSON.stringify() method takes a JavaScript object and converts it into a JSON string. This method is useful when sending data to a web server, as the data must be in string format when sent. The output data cannot be accessed as a JavaScript object.
Here's an example of JSON.stringify():

JSON.parse()

The JSON.parse() method takes a JSON string and transforms it into a JavaScript object. This method is particularly useful when receiving data from a web server in string format, as it allows you to access the data as a JavaScript object
Here's an example of JSON.parse():

Usage

Both JSON.parse() and JSON.stringify() can be used in frontend and backend JavaScript development. In frontend development, you might use JSON.parse() when receiving data from an API and JSON.stringify() when sending data to an API.

In backend development, such as with Node.js, you could use JSON.parse() to convert incoming JSON strings into JavaScript objects and JSON.stringify() to convert JavaScript objects into JSON strings for API responses.

Thumb Rule:

Here's a simple rule of thumb to help you decide when to use JSON.parse() and JSON.stringify():

• Use JSON.parse() when you have a JSON string and need to convert it into a JavaScript object for easier manipulation.

• Use JSON.stringify() when you have a JavaScript object and need to convert it into a JSON string for sending to a server or API.

By following this rule, you can effectively work with JSON data in both frontend and backend JavaScript development.