JavaScript Arithmetic Operators

Last Updated : 22 Nov, 2024

JavaScript Arithmetic Operators are the operator that operate upon the numerical values and return a numerical value.

Addition (+) Operator

The addition operator takes two numerical operands and gives their numerical sum. It also concatenates two strings or numbers.

// Number + Number => Addition 
let x = 1 + 2;
console.log( x );

// Number + String => Concatenation
let y =  5 + "hello"; 
console.log( y );

Output

3
5hello

Subtraction (-) Operator

The subtraction operator gives the difference between two operands in the form of numerical value.

// Number - Number => Subtraction 
let x = 10 - 7;
console.log( x );

let y = "Hello" - 1; 
console.log( y );

Output

3
NaN

**Multiplication (*) Operator**

The multiplication operator gives the product of operands where one operand is a multiplicand and another is multiplier.

// Number * Number => Multiplication
let x = 3 * 3;
let y = -4 * 4; 
console.log(x);
console.log(y);

let a = Infinity * 0;
let b = Infinity * Infinity;
console.log(a);
console.log(b);
let z = 'hi' * 2; 
console.log(z);

Output

9
-16
NaN
Infinity
NaN

Division (/) Operator

The division operator provides the quotient of its operands where the right operand is the divisor and the left operand is the dividend.

// Number / Number => Division
let x = 5 / 2;
let y = 1.0 / 2.0;
console.log(x);
console.log(y);

let a = 3.0 / 0;
let b = 4.0 / 0.0;
console.log(a);
console.log(b);
let z = 2.0 / -0.0;
console.log(z);

Output

2.5
0.5
Infinity
Infinity
-Infinity

Modulus (%) Operator

The modulus operator returns the remainder left over when a dividend is divided by a divisor. The modulus operator is also known as the remainder operator. It takes the sign of the dividend.

// Number % Number => Modulus of the number
let x = 9 % 5;
let y = -12 % 5;
let z = 1 % -2;
let a = 5.5 % 2;
let b = -4 % 2;
let c = NaN % 2;

console.log(x);
console.log(y);
console.log(z);
console.log(a);
console.log(b);
console.log(c);

Output

4
-2
1
1.5
-0
NaN

Exponentiation () Operator**

The exponentiation operator gives the result of raising the first operand to the power of the second operand. The exponentiation operator is right-associative.

In JavaScript, it is not possible to write an ambiguous exponentiation expression i.e. you cannot put an unary operator (+ / – / ~ / ! / delete / void) immediately before the base number.

// Number ** Number => Exponential of the number

// let x = -4 ** 2 // This is an incorrect expression
let y = -(4 ** 2);
let z = 2 ** 5;
let a = 3 ** 3;
let b = 3 ** 2.5; 
let c = 10 ** -2;
let d = 2 ** 3 ** 2; 
let e = NaN ** 2;

console.log(y);
console.log(z);
console.log(a);
console.log(b);
console.log(c);
console.log(d);
console.log(e);

Output

-16
32
27
15.588457268119896
0.01
512
NaN

Increment (++) Operator

The increment operator increments (adds one to) its operand and returns a value.

If used postfix with the operator after the operand (for example, x++), then it increments and returns the value before incrementing.
If used prefix with the operator before the operand (for example, ++x), then it increments and returns the value after incrementing.

// Postfix 
let a = 2;
b = a++; // b = 2, a = 3

// Prefix
let x = 5;
y = ++x; // x = 6, y = 6

console.log(a);
console.log(b);
console.log(x);
console.log(y);

Output

Decrement (- -) Operator

The decrement operator decrements (subtracts one from) its operand and returns a value.

If used postfix, with operator after operand (for example, x–), then it decrements and returns the value before decrementing.
If used prefix, with the operator before the operand (for example, –x), then it decrements and returns the value after decrementing.

// Prefix
let a = 2;
b = --a; 

// Postfix 
let x = 3;
y = x--;
 
console.log(a);
console.log(b);
console.log(x);
console.log(y);

Output

Unary Negation (-) Operator

This is a unary operator i.e. it operates on a single operand. It gives the negation of an operand.

let a = 3;
b = -a; 

// Unary negation operator
// can convert non-numbers
// into a number
let x = "3";
y = -x; 
  
console.log(a);
console.log(b);
console.log(x);
console.log(y);

Output

3
-3
3
-3

Unary Plus (+) Operator

This is a way to convert a non-number into a number. Although unary negation (-) also can convert non-numbers, unary plus is the fastest and preferred way of converting something into a number, because it does not perform any other operations on the number.

let a =  +4;
let b = +'2';   
let c = +true;  
let x = +false; 
let y = +null;
     
console.log(a);
console.log(b);
console.log(c);
console.log(x);
console.log(y);

Output

Arithmetic Operators list

There are many arithmetic operators as shown in the table with the description.

OPERATOR NAME	USAGE	OPERATION
Addition Operator	a + b	Add two numbers or concatenate the string
Subtraction Operator	a – b	Difference between the two operators
Multiplication Operator	a * b	Multiply two number
Division Operator	a / b	Find the quotient of two operands
Modulus Operator	a % b	Find the remainder of two operands
Exponentiation Operator	a ** b	Raise the Left operator to the power of the right operator
Increment Operator	a++ ++a	Return the operand and then increase by one Increase operand by one and then return
Decrement Operator	a- – – -a	Return operand and then decrease by one Decrease operand by one and then return
Unary Plus(+)	+a	Converts NaN to number
Unary Negation (-)	-a	Converts operand to negative.

We have a complete list of Javascript operators, to check those please go through this Javascript Operators Complete reference article.

We have a Cheat Sheet on Javascript where we covered all the important topics of Javascript to check those please go through Javascript Cheat Sheet-A Basic guide to JavaScript.