base64 decode javascript code example

Example 1: base64 decode javascript

var string = "Hello folks how are you doing today?";
var encodedString = btoa(string); // Base64 encode the String
var decodedString = atob(encodedString); // Base64 decode the String

Example 2: base64 to string and string to base64 javascript decode

// base64 to string
let base64ToString = Buffer.from(obj, "base64").toString();
base64ToString = JSON.parse(base64ToString);

//or
let str = 'bmltZXNoZGV1amEuY29t';
let buff = new Buffer(str, 'base64');
let base64ToStringNew = buff.toString('ascii');

// string to base64
let data = 'nimeshdeuja.com';
let buff = new Buffer(data);
let stringToBase64 = buff.toString('base64');

Example 3: javascript base64 decode

// Define the string
var string = 'Hello World!';

// Encode the String
var encodedString = btoa(string);
console.log(encodedString); // Outputs: "SGVsbG8gV29ybGQh"

// Decode the String
var decodedString = atob(encodedString);
console.log(decodedString); // Outputs: "Hello World!"

Example 4: javascript base64 decode

var decodedString = atob(encodedString);

Example 5: javascript base64url decode

var decode = function(input) {
        // Replace non-url compatible chars with base64 standard chars
        input = input
            .replace(/-/g, '+')
            .replace(/_/g, '/');

        // Pad out with standard base64 required padding characters
        var pad = input.length % 4;
        if(pad) {
          if(pad === 1) {
            throw new Error('InvalidLengthError: Input base64url string is the wrong length to determine padding');
          }
          input += new Array(5-pad).join('=');
        }

        return input;
    }