JavaScript Arithmetic Operators

Last Updated: 22 Nov, 2024

JavaScript Arithmetic Operators operate upon 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 a 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 a 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.

// 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 raises the first operand to the power of the second operand.

// Number ** Number => Exponential of the number
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 adds one to its operand and returns a value.

// Postfix 
let a = 2;
b = a++;
 
// Prefix
let x = 5;
y = ++x;
 
console.log(a);
console.log(b);
console.log(x);
console.log(y);

Output:

Decrement (--) Operator

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

// 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 unary operator negates its operand.

let a = 3;
b = -a;
 
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 operator converts non-numbers into numbers.

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

OPERATOR	USAGE	OPERATION
Addition	a + b	Adds two numbers or concatenates strings
Subtraction	a - b	Finds the difference between two operands
Multiplication	a * b	Multiplies two numbers
Division	a / b	Finds the quotient of two operands
Modulus	a % b	Finds the remainder of two operands
Exponentiation	a ** b	Raises left operand to the power of the right operand
Increment	a++ / ++a	Increases operand by one
Decrement	a-- / --a	Decreases operand by one
Unary Plus	+a	Converts NaN to a number
Unary Negation	-a	Converts operand to negative

For a complete reference, check our JavaScript Operators Complete Reference. For a quick overview, visit our JavaScript Cheat Sheet.

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