Sign Up for Free

RunKit +

Try any Node.js package right in your browser

This is a playground to test code. It runs a full Node.js environment and already has all of npm’s 400,000 packages pre-installed, including atob with all npm packages installed. Try it out:

var atob = require("atob")

This service is provided by RunKit and is not affiliated with npm, Inc or the package authors.

atob v2.1.2

atob for Node.JS and Linux / Mac / Windows CLI (it's a one-liner)


| atob | btoa | unibabel.js | Sponsored by ppl

Uses Buffer to emulate the exact functionality of the browser's atob.

Note: Unicode may be handled incorrectly (like the browser).

It turns base64-encoded ascii data back to binary.

(function () {
  "use strict";

  var atob = require('atob');
  var b64 = "SGVsbG8sIFdvcmxkIQ==";
  var bin = atob(b64);

  console.log(bin); // "Hello, World!"

Need Unicode and Binary Support in the Browser?

Check out unibabel.js


  • v2.1.0 address a few issues and PRs, update URLs
  • v2.0.0 provide browser version for ios web workers
  • v1.2.0 provide (empty) browser version
  • v1.1.3 add MIT license
  • v1.1.2 node only


Code copyright 2012-2018 AJ ONeal

Dual-licensed MIT and Apache-2.0

Docs copyright 2012-2018 AJ ONeal

Docs released under Creative Commons.


RunKit is a free, in-browser JavaScript dev environment for prototyping Node.js code, with every npm package installed. Sign up to share your code.
Sign Up for Free