JavaScript Operators

Name

Description

Syntax

Example

Addition (+)

Addition ‘+’ operator performs addition on two operands. This ‘+’ operator can also be used to concatenate (add) strings.

Y = “Geeks” + “for” + “Geeks” gives Y = “GeeksforGeeks” Y

Subtraction (-)

Subtraction ‘-‘ operator performs subtraction on two operands.

Y = 5 – 3 gives Y = 2

Multiplication (*)

Multiplication ‘*’ operator performs multiplication on two operands.

Y = 5 * 5 gives Y = 25

Division (/) 

Division ‘/’ operator performs division on two operands (divide the numerator by the denominator).

Y = 5 / 5 gives Y = 1

Modulus (%)

Modulus ‘%’ operator gives a remainder of an integer division. 

A % B means remainder (A/B) Y = 5 % 4 gives Y = 1

Exponentiation (**)

Exponentiation ‘**’ operator give the power of the first operator raised to the second operator.

Y = 5 ** 3 gives Y = 125

Increment(++)

Increment ‘+ +’ operator increases an integer value by one. 

let A = 10 and Y = A + + then A = 11, Y=10

Decrement (–)

Decrement ‘- -‘ operator decreases an integer value by one.

let A = 10 and Y = A – – then A = 9, Y=10

Unary (+)

Unary ‘+’ is the fastest and preferred way of converting something into a number

+a means a is a positive number

Negation (-)

Negation ‘-‘ operator gives the negation of an operand.

-a means a is a negative number

Name

Description

Syntax

Example

Assignment (=)

This operator assigns the right operand value to the left operand.

If A = 10 and Y = A then Y = 10

Addition Assignment (+=)

Sums up left and right operand values and then assigns the result to the left operand.

Y += 1 gives Y = Y + 1

Subtraction Assignment (-=)

It subtracts the right side value from the left side value and then assigns the result to the left operand. 

Y -= 1 gives Y = Y – 1

Multiplication Assignment (*=)

It multiplies a variable by the value of the right operand and assigns the result to the variable.

Y *= A is equivalent to Y = Y * A

Division Assignment (/=)

It divides a variable by the value of the right operand and assigns the result to the variable.

Y /= A is equivalent to Y = Y / A

Modules/Remainder Assignment (%=)

It divides a variable by the value of the right operand and assigns the remainder to the variable.

Y %= A is equivalent to Y = Y % A

Exponentiation Assignment (**=)

This raises the value of a variable to the power of the right operand.

Y **= A is equivalent to Y=Y ** A

Left Shift Assignment (<<=)

It moves the specified amount of bits to the left and assigns the result to the variable.

Y <<= A is equivalent to Y=Y << A

Right Shift Assignment (>>=)

It moves the specified amount of bits to the right and assigns the result to the variable.

Y >>= A is equivalent to Y = Y >> A

Bitwise AND Assignment (&=)

: It does a bitwise AND operation on the operand, and assigns the result to the variable.

Y &= b is equivalent to Y = Y & A

Bitwise OR Assignment (|=)

It does a bitwise OR operation on the operand, and assigns the result to the variable.

Y |= A is equivalent to Y= Y | b

Bitwise XOR Assignment (^=)

It does a bitwise XOR operation on the operand, and assigns the result to the variable.

Y ^= A is equivalent to Y= Y ^ A

Name

Description

Syntax

Example

Equality (==)

Compares the equality of two operands. If equal then the condition is true otherwise false.

Y = 5 and X = 6 Y = = X is false.

Strict equality (===)

Compares the equality of two operands with type. If both value and type are equal then the condition is true otherwise false.

Y = 5 and X = ‘5’ Y = = = X is false.

Inequality (!=)

Compares inequality of two operands. True if operands are not equal. 

let X = 10 then X ! = 11 is true.

Strict inequality (!==)

Compares the inequality of two operands with type. If both value and type are equal then the condition is true otherwise false.

let X = 10 then X ! == ’10’ is true.

Greater than (>)

This operator checks whether the left side value is greater than the right side value. If yes then it returns true otherwise it returns false. 

let X = 10 then X > 11 is false.

Less than (<)

This operator checks whether the left side value is less than the right side value. If yes then it returns true otherwise it returns false. 

let X = 10 then X < 11 is true.

Greater than or Equal to (>=)

This operator checks whether the left side operand is greater than or equal to the right side operand. If yes then it returns true otherwise it returns false. 

let X = 10 then X > = 11 is false.

Less than or Equal to (<= )

This operator checks whether the left side operand value is less than or equal to the right side operand value. If yes then it returns true otherwise it returns false. 

let X = 10 then X < = 10 is true.

Name

Description

Syntax

Example

Logical AND (&&)

It checks whether two operands are non-zero (0, false, undefined, null, or “” are considered as zero), if yes then return the last operand when evaluating from left to right

Y = 5 and X = 6 Y && X is 6.

Logical OR (||)

It checks whether two operands are non-zero (0, false, undefined, null, or “” is considered as zero), if yes then return the first operand when evaluating from left to right. 

Y = 5 and X = 0 Y || X is 5.

Logical NOT (!) 

It reverses the boolean result of the operand (or condition).

Y = 5 and X = 0 !(Y || X) is false.

Name

Description

Syntax

Example

Bitwise AND (&)

The operator returns true only if both the operands are true

A = 6, B=1 A&B = 0

Bitwise OR (|)

The operator returns true even if one of the operands is true 

A = 6, B=1 A|B = 7

Bitwise XOR (^)

The operator returns true if both operators are distinct

A = 6, B=1 A^B = 7

Bitwise NOT (~)

This operator is used to invert the boolean value of the operand

A = 6 ~A = -7

Bitwise Left Shift (<<)

In this two operators are used where the first operand is the number and the second operand is the number of bits to shift to the left.

A = 6, B=1 A<<B = 12

Bitwise Right Shift (>>)

In this two operators are used where the first operand is the number and the second operand is the number of bits to shift to the right.

A = 6, B=1 A>>B = 3

Zero Fill Right Shift (>>>)

It is same as a bitwise right shift the only difference is that overflowing bits are discarded.

A = 6, B=1 A>>>B = 3

Name

Description

Syntax

Example

Ternary Operator (?:)

It is like the short form of the if-else condition. 

Y = ? A : B If the condition is true then Y = A otherwise Y = B

Name

Description

Syntax

Example

 comma operator (,)

When a comma operator is placed in an expression, it executes each expression and returns the rightmost expression.

Expression1, Expression2, Expression3, …so on

Name

Description

Syntax

Example

JavaScript typeof

It returns the operand type, The possible types that exist in javascript are undefined, Object, boolean, number, string, symbol, and function.

typeof variable

Delete

This operator is more specifically used to delete JavaScript object properties.

delete object

// or

delete object.property

// or

delete object[‘property’]

Name

Description

Syntax

Example

in

The in operator returns true if the specified property is in the specified object.

propNameOrNumber in objectName

instanceof

The instanceof operator returns true if the specified object is of the specified object type.

objectName instanceof objectType

Name

Description

Syntax

Example

BigInt

It returns a new BigInt object that represents the original value.

BigInt(value);

Name

Description

Syntax

Example

 concatenation operator (+)

It concatenates two string values together, returning another string that is the union of the two operand strings.

str1 + str2

Safely accesses properties, methods, or

array elements of deeply nested objects.

If any part of the chain is null or undefined,

it returns undefined instead

let result = object?.property

let user = {

name: “John”, address: { city: “New York” }};

console.log(user?.address?.city);

console.log(user?.address?.zipcode);