cryptoRandom(), a secure alternative to Math.random() utilising the Web Crypto API.

cryptorandom.js

function cryptoRandom() {
	const cryptoObj = crypto || window.crypto || window.msCrypto;
	const genArray = cryptoObj.getRandomValues(new Uint8Array(7));
	let tmpArray = [];

	genArray.forEach(function(ele, index) {
		tmpArray[index] = ele.toString();
		if (ele.toString().length < 3) {
			if (((index === 0) && (Math.random() < 0.1)) || (Math.random() < 0.5)) {
				tmpArray[index] = ("0" + ele);
			}
		}
	});

	return Number("0." + tmpArray.join(""));
}