How to create a secure random number using JavaScript?

To create a secure random number, we will use getRandomValues() method from window.crypto

Step 1: Get a random number using getRandomValues()

var cryptoRandom = window.crypto.getRandomValues(new Uint32Array(1))[0];

console.log(cryptoRandom);

// 2557767905

Step 2: Divide that number with a similar large number.

To do we need to use JavaScript pow() Method. It returns the value of x to the power of y.

After division, we will get the random number in a fraction of a zero.

var cryptoRandom2 = cryptoRandom / (Math.pow(2, 32) - 1);

console.log(cryptoRandom2);

// 0.8196058019110015

Step 3: Multiply with 10 to remove the fraction.

cryptoRandom3 = cryptoRandom2 * 10;

console.log(cryptoRandom3);

// 8.175500582013163

Step 4: Use Math.floor to get single digit random number.

console.log(Math.floor(cryptoRandom3));

// 8

NOTE: If you run the code chunks separately then you will get a different number each time. 

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