Base64 encoding is a process of converting binary data into a set of ASCII characters. This encoding technique is often used for transmitting data over the internet, including images, audio files, and other multimedia data. In this tutorial, we will learn how to Base64 encode in JavaScript.

Using the btoa() Method

JavaScript provides a built-in method called btoa() that encodes a string using Base64. Here is an example of how to use the btoa() method:

let text = "Hello, World!";
let encodedText = btoa(text);
console.log(encodedText); // Outputs "SGVsbG8sIFdvcmxkIQ=="

In this example, we first define a string called “Hello, World!”. We then use the btoa() method to encode the string and store the result in a variable called encodedText. Finally, we log the encoded text to the console.

Using the Base64 Encoding Library

If you need to encode binary data, such as an image or audio file, you can use a Base64 encoding library. One popular library is the js-base64 library, which can be installed using npm:

npm install js-base64

Once you have installed the library, you can use it to encode binary data as follows:

import { Base64 } from 'js-base64';

let binaryData = ... // binary data to be encoded
let encodedData = Base64.encode(binaryData);

In this example, we first import the Base64 object from the js-base64 library. We then define a variable called binaryData, which represents the binary data that we want to encode. We use the Base64.encode() method to encode the binary data and store the result in a variable called encodedData. Finally, we log the encoded data to the console.


Base64 encoding is a useful technique for transmitting binary data over the internet. In this tutorial, we learned how to base64 encode in JavaScript using the built-in btoa() method and the js-base64 library. By understanding how to use these tools, you can easily encode and transmit data in your JavaScript applications.