JavaScript Assignment Operators

The JavaScript Assignment operators are used to assign values to the declared variables. Equals (=) operator is the most commonly used assignment operator. For example:

var i = 10;

The below table displays all the JavaScript assignment operators.

JavaScript Assignment OperatorsExampleExplanation
=x = 15Value 15 is assigned to x
+=x += 15This is same as x = x + 15
-=x -= 15This is same as x = x – 15
*=x *= 15This is same as x = x * 15
/=x /= 15This is same as x = x / 15
%=x %= 15This is same as x = x % 15

JavaScript Assignment Operators Example

For this example, We are using two integer variables a, and Total, and their values are 7 and 21. We are going to use these two variables to show you the working functionality of all the Assignment Operators in JS.

<!DOCTYPE html>
<html>
<head>
    <title> JavascriptAssignmentOperators</title>
</head>
<body>
    <h1> AssignmentOperations </h1>
<script>
   var a = 7, Total = 21;

   document.write("Value of the Total = " + (Total += a) + "<br />");
   document.write("Value of the Total = " + (Total -= a) + "<br />");
   document.write("Value of the Total = " + (Total *= a) + "<br />");   
   document.write("Value of the Total = " + (Total /= a) + "<br />");
   document.write("Value of the Total = " + (Total %= a) + "<br />");
</script>
</body>
</html>
JavaScript Assignment Operators 1

In this JavaScript Assignment Operators program, We declared 2 integer values a, and Total, and we assigned values 7 and 21 respectively. Below statements will perform Assignment operations on a and Total and then write the output to the respective browser.

Let us see the functionality of the JS Assignment Operators

document.write("Value of the Total = " + (Total += a) + "<br />");

Total += a means

Total = Total + a = 21 + 7 = 28

document.write("Value of the Total = " + (Total -= a) + "<br />");

Total -= a means

Total = Total – a = 28 – 7 = 21

document.write("Value of the Total = " + (Total *= a) + "<br />");

Total *= a means

Total = Total * a = 21 * 7 = 147

document.write("Value of the Total = " + (Total /= a) + "<br />");

Total /= a means

Total = Total / a = 147 / 7 = 21

document.write("Value of the Total = " + (Total %= a) + "<br />")

Total %= a means

Total = Total + a = 21 % 7 = 0 (Remainder of 21/7 is = 0)

JavaScript Assignment Operators Example 2

For this JavaScript example, we are using two integer variables, a and Total, whose values are 7 and 21. We will use these variables to show you, How to display the Assignment Operators output in Paragraphs.

<!DOCTYPE html>
<html>
<head>
    <title> Example 2</title>
</head>
<body>
    <h1> Assignment Operations </h1>
    <p id = 'add'> Plus Equal to </p>
    <p id = 'sub'> Subtraction Equal to </p>
    <p id = 'mul'> Multiplication Equal to </p>
    <p id = 'div'> Division Equal to </p>
    <p id = 'mod'> Modulus Equal to </p>
<script>
   var a = 3, Total = 12;

   document.getElementById("add").innerHTML = "Value of the Total = " + (Total += a);
   document.getElementById("sub").innerHTML = "Value of the Total = " + (Total -= a);
   document.getElementById("mul").innerHTML = "Value of the Total = " + (Total *= a);
   document.getElementById("div").innerHTML = "Value of the Total = " + (Total /= a);
   document.getElementById("mod").innerHTML = "Value of the Total = " + (Total %= a);

</script>
</body>
</html>
Assignment Operations

Value of the Total = 15

Value of the Total = 12

Value of the Total = 36

Value of the Total = 12

Value of the Total = 0