random number javascript code example

Example 1: math.random javascript

Math.random() 
// will return a number between 0 and 1, you can then time it up to get larger numbers.
//When using bigger numbers remember to use Math.floor if you want it to be a integer
Math.floor(Math.random() * 10) // Will return a integer between 0 and 9
Math.floor(Math.random() * 11) // Will return a integer between 0 and 10

// You can make functions aswell 
function randomNum(min, max) {
	return Math.floor(Math.random() * (max - min)) + min; // You can remove the Math.floor if you don't want it to be an integer
}

Example 2: javascript get random number in range

function getRandomNumberBetween(min,max){
    return Math.floor(Math.random()*(max-min+1)+min);
}

//usage example: getRandomNumberBetween(20,400);

Example 3: random number javascript

/* 
   The Math.random() function returns a floating-point, pseudo-random
   number in the range 0 to less than 1 (inclusive of 0, but not 1)
   with approximately uniform distribution over that range — which you
   can then scale to your desired range. The implementation selects the
   initial seed to the random number generation algorithm; it cannot
   be chosen or reset by the user.
*/
function getRandomInt(max) {
   return Math.floor(Math.random() * Math.floor(max));
}

console.log(getRandomInt(3));
// expected output: 0, 1 or 2

console.log(getRandomInt(1));
// expected output: 0

console.log(Math.random());
// expected output: a number from 0 to <1

Example 4: generate random integer javascript

var randomnumber = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;