To read a JSON file in JavaScript, you can use the “require()”, “fetch()”, or “loadJSON()” function.
Method 1: Using a require() function
To load files and modules in Javascript, use the require() function. The require() function takes the path of the file, and with the help of the console.log() function, it displays the data on the server.
Example
const jsonFile = require("./employee.json");
console.log(jsonFile);
Output
{
employees: [
{ firstName: 'Riya', lastName: 'Sharma' },
{ firstName: 'Salman', lastName: 'Singh' },
{ firstName: 'Rahul', lastName: 'Khan' }
]
}
Here we are taking an example employee.json file given below. Put this file inside your current project directory.
{
"employees": [
{
"firstName": "Riya",
"lastName": "Sharma"
},
{
"firstName": "Salman",
"lastName": "Singh"
},
{
"firstName": "Rahul",
"lastName": "Khan"
}
]
}
Method 2: Using the fetch() function
The fetch() is a built-in JavaScript function that fetches a file from the given path we specify and returns the file using the console.log() function. The fetch() function works only in web-based environments as API works only in web-based environments.
Example
import fetch from 'node-fetch';
fetch("./employee.json")
.then(response => {
return response.json();
})
.then(jsondata => console.log(jsondata));
Output
{
employees: [
{ firstName: 'Riya', lastName: 'Sharma' },
{ firstName: 'Salman', lastName: 'Singh' },
{ firstName: 'Rahul', lastName: 'Khan' }
]
}
Method 3: Using the loadJSON() function
The loadJSON() is a built-in JavaScript function used to read the contents of a JSON file or URL and return it as an object. The loadJSON() function is asynchronous; therefore, it is recommended to be called in the preload() function to ensure it is executed before the other functions.
Syntax
loadJSON(link, function, optional)
Arguments
The loadJSON() function accepts three parameters:
- Link: In this, we specify the URL of the Page where JSON data is present.
- Function: This is the function to which the data read by URL will be transferred.
- Optional: This is an optional parameter in the loadJSON() function that is used to define data security sometimes.
Example
loadJSON("https://jsonplaceholder.typicode.com/posts", getData, 'jsonp');
function getData(Data) {
console.log(Data[0]);
}
That’s it.

Niva Shah is a Software Engineer with over eight years of experience. She has developed a strong foundation in computer science principles and a passion for problem-solving.