JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://crypto-js.googlecode.com/svn/tags/3.0.2/build/rollups/hmac-sha256.js"></script>
<script src="http://crypto-js.googlecode.com/svn/tags/3.0.2/build/components/enc-base64-min.js"></script>

JavaScript

var hash1 = CryptoJS.HmacSHA256("st=1453362060~exp=1453363260~acl=/*", String.fromCharCode(63));
var hash2 = CryptoJS.HmacSHA256("st=1453362060~exp=1453363260~acl=/*", String.fromCharCode(63) + String.fromCharCode(23));
var hash3 = CryptoJS.HmacSHA256("st=1453362060~exp=1453363260~acl=/*", String.fromCharCode(63) + String.fromCharCode(23) + String.fromCharCode(253));

document.write(hash1.toString() + "<br>");
document.write(hash2.toString() + "<br>");
document.write(hash3.toString() + "<br>");