json.parse vs json.stringify example

Difference between JSON.stringify and JSON.parse

stackoverflow.com › questions › 17785592 › difference-between-json-stringify-and-json-parse

JSON.stringify turns a JavaScript object into JSON text and stores that JSON text in a string, eg:

var my_object = { key_1: "some text", key_2: true, key_3: 5 };

var object_as_string = JSON.stringify(my_object);  
// "{"key_1":"some text","key_2":true,"key_3":5}"  

typeof(object_as_string);  
// "string"

JSON.parse turns a string of JSON text into a JavaScript object, eg:

var object_as_string_as_object = JSON.parse(object_as_string);  
// {key_1: "some text", key_2: true, key_3: 5} 

typeof(object_as_string_as_object);  
// "object"

Answer from Quentin on Stack Overflow

Stack Overflow

stackoverflow.com › questions › 17785592 › difference-between-json-stringify-and-json-parse

Difference between JSON.stringify and JSON.parse

Top answer

1 of 16

715

JSON.stringify turns a JavaScript object into JSON text and stores that JSON text in a string, eg:

var my_object = { key_1: "some text", key_2: true, key_3: 5 };

var object_as_string = JSON.stringify(my_object);  
// "{"key_1":"some text","key_2":true,"key_3":5}"  

typeof(object_as_string);  
// "string"

JSON.parse turns a string of JSON text into a JavaScript object, eg:

var object_as_string_as_object = JSON.parse(object_as_string);  
// {key_1: "some text", key_2: true, key_3: 5} 

typeof(object_as_string_as_object);  
// "object"

2 of 16

JSON.parse() is for "parsing" something that was received as JSON.
JSON.stringify() is to create a JSON string out of an object/array.

Built In

builtin.com › software-engineering-perspectives › json-stringify

How to Use JSON.stringify() and JSON.parse() in JavaScript | Built In

Summary: JSON.stringify() converts a JavaScript object into a JSON string, and JSON.parse() reverses the process. These methods are often used together to handle JSON data, but they don’t support certain types like undefined, Infinity, NaN, ...

Discussions

Difference between JSON.stringify and JSON.parse - Studytonight

I have been confused over when to use these two parsing methods. After I echo my json_encoded data and retrieve it back via ajax, I often run into confusion about when I should use JSON.stringify and JSON.parse. More on studytonight.com

studytonight.com

June 1, 2021

Trying to learn fetch(), JSON.stringify() confusion

You use express.json middleware which tried to parse the body as JSON. hello is not valid JSON. More on reddit.com

r/learnjavascript

December 1, 2020

What is happening when I call JSON and JSON.stringify in the console?

Have you figured out the JSON format? It has a few simple constructs with the same syntax that JS uses: Objects: {} Arrays: [] Numbers: 123 Strings: "123" Booleans: true Null: null Objects have fields which can be any of the above constructs, eg: { "field": "value", "anotherField": 123.456 } Similarly, arrays can contain any of the above constructs as members, eg: [ "Hello", "World", false, null ] The fact that these two constructs can contain any of the other constructs is where the recursion comes in. So an object can contain another object, etc. Eg: [ { "field": "value", "anotherField": 123.456 } "foo", [1, 2, 3] ] Anyway, I'm sure you're aware of how this maps perfectly to how JS objects work. Your job is to take some arbitrary JS object and convert it into JSON like the examples above. The recursion comes from the fact that for every field in an object or element in an array, you must convert that field/element to JSON, too! The base case is when you have an object or array that is empty or one of the leaf types (Number, String, or Boolean). Just note that you'd have to escape the contents of strings to ensure you end up with valid JSON. Normally you'd do this with JSON.stringify, but that's probably a no-go since you're implementing your own version of that function. I believe you should be able to get by with escaping just \ (to \\) and " (to \"). More on reddit.com

r/learnprogramming

September 17, 2015

JSON.stringify got faster

That’s a big win for something so widely used. crazy how many apps get faster just because V8 optimized a single function. More on reddit.com

r/programming

347

July 10, 2025

Videos