JavaScript Remainder(%) Operator

The remainder operator in JavaScript is used to get the remaining value when an operand is divided by another operand. In some languages, % is considered modulo. Modulo and Remainder work differently when the sign of both operands is different.

In JavaScript remainder takes the sign of the dividend and to get modulo ((a % n) + n) % n should be used instead of a % n.

Syntax

remainder = var1 % var2

Example 1: This example returns the positive remainder in this case both modulo and remainder will be the same as both operands are positive.

Javascript

<script>
    // Initializing variables
    var a =4
    var n = 2

    // Calculating remainder
    var rem = a%n

    // Calculating modulo
    var mod = ((a%n)+n)%n

    // Printing result
    console.log("Remainder is "+rem)
    console.log("Modulo is "+mod)
</script>

Output:

"Remainder is 0"
"Modulo is 0"

Example 2: This example returns a negative remainder as the dividend is negative.

Javascript

<script>
    // Initializing variables
    var a =-4
    var n = 2

    // Calculating remainder
    var rem = a%n

    // Calculating modulo
    var mod = ((a%n)+n)%n

    // Printing result
    console.log(rem)
    console.log(mod)
</script>

Output:

-0
0

Example 3: Remainder with Infinity and NaN

Javascript

<script>
    // Both operands are NaN
    console.log(NaN%NaN)

    // Dividend is NaN
    console.log(NaN%2)

    // Dividend is Nan and Divisor is Infinity
    console.log(NaN%Infinity)

    // Dividend is Infinity and Divisor is NaN
    console.log(Infinity%NaN)

    // Both operands are Infinity
    console.log(Infinity%Infinity)

    // Dividend is infinity
    console.log(Infinity%5)
</script>

Output:

NaN
NaN
NaN
NaN
NaN
NaN

We have a complete list of Javascript Operators, to check those please go through the Javascript Operators Complete Reference article.