How to Base64 Encode a String in Node.js?

The easiest way to encode a string to base64 in Node.js is to use the built-in Buffer object. For example:

const str = 'foobar';
const base64EncodedStr = Buffer.from(str).toString('base64');

console.log(base64EncodedStr); // output: 'Zm9vYmFy'

Since the Buffer object is within the global scope, you do not need to use require('buffer').Buffer.

Please note that in versions of Node.js below 6.0.0, the syntax "new Buffer(string[, encoding])" was commonly used. However, using the constructor to instantiate a new Buffer object was deprecated starting from Node.js v6.0.0 as it was vulnerable to "Remote Memory Disclosure" attacks. You should instead use Buffer.from().