Generate random integer between two numbers using JavaScript
Random number generation is the generation of a sequence of numbers or symbols that cannot be reasonably predicted better than by a random chance, usually through a random-number generator (RNG). Computer random number generators are important in mathematics, cryptography and gambling (on game servers).
In this article, we will be generating a random integer between given two numbers using JavaScript. We will be generating a random number in a given range using JavaScript Math Object.
We often need to generate a random number within a specified range in realtime applications. The logic dealt below can be very useful in situations like this.
Fundamental Concept
Math.floor(Math.random() * ((y-x)+1) + x);
Math.random() returns a random number between 0 (inclusive) and 1 (exclusive).
Math.floor() rounds a number downward to its nearest integer.
Generating JavaScript random number
CSS:
.highlight{ color:green; }
HTML:
<h1>Generate Random Number Using JavaScript</h1> Random Number Between and <input type=”button” value=”Get Number” onclick=”getRandomNumber();”> <h2 class=”number”></h2>
JavaScript:
function getRandomNumberBetween(start,end){ return Math.floor(Math.random()*(end-start+1))+start; } function getRandomNumber(){ var start = document.getElementsByClassName('start')[0].value; var end = document.getElementsByClassName('end')[0].value; document.getElementsByClassName('number')[0].innerHTML = 'The Random Number is : <span class="highlight">'+getRandomNumberBetween(parseInt(start),parseInt(end))+'</span>'; }
In this way, we can generate random integer between two numbers using JavaScript.
You can follow the video for detail instructions and demo: