The Math.random() JavaScript method returns a floating-point random number between 0 (inclusive) and 1 (not included).
This method can be used to generate random integer numbers in JavaScript.
Bellow there are 3 functions with examples to generate random integer numbers with various criterias.


Examples random numbers in JS

1. The randomNr() function from the following example returns a random integer between a minimum and maximum number.
//Returns a random integer between min (inclusive) and max (inclusive)
function randomNr(min, max){
 return Math.floor(Math.random() * (max - min + 1)) + min;
}

//Test
var nr_al = randomNr(1, 9999);
document.write(nr_al); //78 /355 /7098
2. The randNrDigits() function presented in the following example returns a random integer with a specified number of digits.
//Returns a random integer with a specified number of digits (nd)
function randNrDigits(nd){
 var n0 =1;
 for(var i=1; i<nd; i++) n0 +='0';
 return Math.floor((1*n0) + Math.random() * (9*n0));
}

//Test
var nr_al = randNrDigits(4);
document.write(nr_al); //3424
3. The randNrUniqueDigits() function from the following example returns a random integer with a specified number of digits, and the digits do not repeat.
//Returns a random integer with digits that not repeat, with specified number of digits (nd)
function randNrUniqueDigits(nd){
 var ar_nr =[0,1,2,3,4,5,6,7,8,9];
 for(let i = ar_nr.length -1; i >0; i--){
 let j = Math.floor(Math.random() * (i + 1)); 
 [ar_nr[i], ar_nr[j]] = [ar_nr[j], ar_nr[i]];
 }

 return ar_nr.splice(1, nd).join('')*1;
}

//Test
var nr_al = randNrUniqueDigits(4);
document.write(nr_al); //5940

Daily Test with Code Example

HTML
CSS
JavaScript
PHP-MySQL
Which attribute indicates that an input field must be filled out before submitting?
required="required" autofocus="autofocus" placeholder="text"
<input type="text" name="name1" required="required" />
Which CSS method increases or decreases the size of the HTML element (including its content)?
translate() scale() skew()
#some_id:hover {
  transform: scale(2, 1.5);
  -ms-transform: scale(2, 1.5);    /* IE 9 */
  -moz-transform: scale(2, 1.5);   /* Firefox */
}
Click on the Date object method that returns the day of the month.
setDate() getMonth() getDate()
var rightnow = new Date();
var day = rightnow.getDate();
alert(day);
Which function is used to upload a file on server?
is_file() move_uploaded_file() fopen()
if(move_uploaded_file($_FILES["field_name"]["tmp_name"], "dir/file_name")) {
  echo "The file succesfully uploaded";
}
Generate random numbers in JavaScript

Last accessed pages

  1. Wake Up! (3403)
  2. Ajax-PHP Chat Script (37775)
  3. PHP-MySQL Scripts (3924)
  4. Create simple Website with PHP (20532)
  5. Select in MySQL, Output results in HTML Table (5636)

Popular pages this month

  1. Insert, Select and Update NULL value in MySQL (415)
  2. Read Excel file data in PHP - PhpExcelReader (331)
  3. PhpSpreadsheet - Read, Write Excel and LibreOffice Calc files (257)
  4. PHP getElementById and getElementsByTagName (208)
  5. Courses Web: PHP-MySQL JavaScript Node.js Ajax HTML CSS (199)