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Assignment operators assign values to JavaScript variables.

Shift Assignment Operators

Bitwise assignment operators, logical assignment operators, the = operator.

The Simple Assignment Operator assigns a value to a variable.

Simple Assignment Examples

The += operator.

The Addition Assignment Operator adds a value to a variable.

Addition Assignment Examples

The -= operator.

The Subtraction Assignment Operator subtracts a value from a variable.

Subtraction Assignment Example

The *= operator.

The Multiplication Assignment Operator multiplies a variable.

Multiplication Assignment Example

The **= operator.

The Exponentiation Assignment Operator raises a variable to the power of the operand.

Exponentiation Assignment Example

The /= operator.

The Division Assignment Operator divides a variable.

Division Assignment Example

The %= operator.

The Remainder Assignment Operator assigns a remainder to a variable.

Remainder Assignment Example

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The <<= Operator

The Left Shift Assignment Operator left shifts a variable.

Left Shift Assignment Example

The >>= operator.

The Right Shift Assignment Operator right shifts a variable (signed).

Right Shift Assignment Example

The >>>= operator.

The Unsigned Right Shift Assignment Operator right shifts a variable (unsigned).

Unsigned Right Shift Assignment Example

The &= operator.

The Bitwise AND Assignment Operator does a bitwise AND operation on two operands and assigns the result to the the variable.

Bitwise AND Assignment Example

The |= operator.

The Bitwise OR Assignment Operator does a bitwise OR operation on two operands and assigns the result to the variable.

Bitwise OR Assignment Example

The ^= operator.

The Bitwise XOR Assignment Operator does a bitwise XOR operation on two operands and assigns the result to the variable.

Bitwise XOR Assignment Example

The &&= operator.

The Logical AND assignment operator is used between two values.

If the first value is true, the second value is assigned.

Logical AND Assignment Example

The &&= operator is an ES2020 feature .

The ||= Operator

The Logical OR assignment operator is used between two values.

If the first value is false, the second value is assigned.

Logical OR Assignment Example

The ||= operator is an ES2020 feature .

The ??= Operator

The Nullish coalescing assignment operator is used between two values.

If the first value is undefined or null, the second value is assigned.

Nullish Coalescing Assignment Example

The ??= operator is an ES2020 feature .

Test Yourself With Exercises

Use the correct assignment operator that will result in x being 15 (same as x = x + y ).

Start the Exercise

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JavaScript operators are special symbols that perform unique operations on one or more operands (values). For example,

The + operator performs addition, we have used it here to add the operands 2 and 3 .

JavaScript Operator Types

Here is a list of different JavaScript operators you will learn in this tutorial:

• Arithmetic Operators
• Assignment Operators
• Comparison Operators
• Logical Operators
• Bitwise Operators
• String Operators
• Miscellaneous Operators

1. JavaScript Arithmetic Operators

We use arithmetic operators to perform arithmetic calculations like addition, subtraction, etc. For example,

Here, we used the - operator to subtract 3 from 5 .

Commonly Used Arithmetic Operators

Example 1: arithmetic operators in javascript, example 2: javascript increment and decrement operators.

To learn more about the increment and decrement operators, visit Increment ++ and Decrement -- Operators .

2. JavaScript Assignment Operators

We use assignment operators to assign values to variables. For example,

Here, we used the = operator to assign the value 5 to variable x .

Commonly Used Assignment Operators

Example 3: assignment operators in javascript, 3. javascript comparison operators.

We use comparison operators to compare two values and return a boolean value ( true or false ). For example,

Here, we have used the > comparison operator to check whether a (whose value is 3 ) is greater than b (whose value is 2 ).

Since 3 is greater than 2 , we get true as output.

Commonly Used Comparison Operators

Example 4: comparison operators in javascript.

The equality operators ( == and != ) convert both operands to the same type before comparing their values. For example,

Here, we used the == operator to compare the number 3 and the string 3 .

By default, JavaScript converts string 3 to number 3 and compares the values.

However, the strict equality operators ( === and !== ) do not convert operand types before comparing their values. For example,

Here, JavaScript didn't convert string 4 to number 4 before comparing their values.

Thus, the result is false , as number 4 isn't equal to string 4 .

4. JavaScript Logical Operators

We use logical operators to perform logical operations on boolean values. For example,

Here, && is the logical operator AND . Since both x < 6 and y < 5 are true , the combined result is true .

Commonly Used Logical Operators

Example 5: logical operators in javascript.

Note: We use comparison and logical operators in decision-making and loops. You will learn about them in detail in later tutorials.

We use bitwise operators to perform binary operations on integers.

Note: We rarely use bitwise operators in everyday programming. If you are interested, visit JavaScript Bitwise Operators to learn more.

6. JavaScript String Operators

In JavaScript, you can use the + operator to concatenate (join) two or more strings . For example,

Here, we used + on strings to perform concatenation. However, when we use + with numbers, it performs addition.

7. JavaScript Miscellaneous Operators

JavaScript has many more operators besides the ones we listed above.

Thus, we have categorized them as miscellaneous operators. You will learn them in detail in later tutorials.

Commonly Used Miscellaneous Operators

• JavaScript typeof Operator

Table of Contents

• Introduction
• JavaScript Arithmetic Operators
• JavaScript Assignment Operators
• JavaScript Comparison Operators
• JavaScript Logical Operators
• JavaScript String Operators
• JavaScript Miscellaneous Operators

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• Assignment operators

An assignment operator assigns a value to its left operand based on the value of its right operand.

The basic assignment operator is equal ( = ), which assigns the value of its right operand to its left operand. That is, x = y assigns the value of y to x . The other assignment operators are usually shorthand for standard operations, as shown in the following definitions and examples.

Simple assignment operator which assigns a value to a variable. The assignment operation evaluates to the assigned value. Chaining the assignment operator is possible in order to assign a single value to multiple variables. See the example.

Addition assignment

The addition assignment operator adds the value of the right operand to a variable and assigns the result to the variable. The types of the two operands determine the behavior of the addition assignment operator. Addition or concatenation is possible. See the addition operator for more details.

Subtraction assignment

The subtraction assignment operator subtracts the value of the right operand from a variable and assigns the result to the variable. See the subtraction operator for more details.

Multiplication assignment

The multiplication assignment operator multiplies a variable by the value of the right operand and assigns the result to the variable. See the multiplication operator for more details.

Division assignment

The division assignment operator divides a variable by the value of the right operand and assigns the result to the variable. See the division operator for more details.

Remainder assignment

The remainder assignment operator divides a variable by the value of the right operand and assigns the remainder to the variable. See the remainder operator for more details.

Exponentiation assignment

This is an experimental technology, part of the ECMAScript 2016 (ES7) proposal. Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future version of browsers as the spec changes.

The exponentiation assignment operator evaluates to the result of raising first operand to the power second operand. See the exponentiation operator for more details.

Left shift assignment

The left shift assignment operator moves the specified amount of bits to the left and assigns the result to the variable. See the left shift operator for more details.

Right shift assignment

The right shift assignment operator moves the specified amount of bits to the right and assigns the result to the variable. See the right shift operator for more details.

Unsigned right shift assignment

The unsigned right shift assignment operator moves the specified amount of bits to the right and assigns the result to the variable. See the unsigned right shift operator for more details.

Bitwise AND assignment

The bitwise AND assignment operator uses the binary representation of both operands, does a bitwise AND operation on them and assigns the result to the variable. See the bitwise AND operator for more details.

Bitwise XOR assignment

The bitwise XOR assignment operator uses the binary representation of both operands, does a bitwise XOR operation on them and assigns the result to the variable. See the bitwise XOR operator for more details.

Bitwise OR assignment

The bitwise OR assignment operator uses the binary representation of both operands, does a bitwise OR operation on them and assigns the result to the variable. See the bitwise OR operator for more details.

Left operand with another assignment operator

In unusual situations, the assignment operator (e.g. x += y ) is not identical to the meaning expression (here x = x + y ). When the left operand of an assignment operator itself contains an assignment operator, the left operand is evaluated only once. For example:

Specifications

Browser compatibility.

• Arithmetic operators

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Home » JavaScript Tutorial » JavaScript Logical Assignment Operators

JavaScript Logical Assignment Operators

Summary : in this tutorial, you’ll learn about JavaScript logical assignment operators, including the logical OR assignment operator ( ||= ), the logical AND assignment operator ( &&= ), and the nullish assignment operator ( ??= ).

ES2021 introduces three logical assignment operators including:

• Logical OR assignment operator ( ||= )
• Logical AND assignment operator ( &&= )
• Nullish coalescing assignment operator ( ??= )

The following table shows the equivalent of the logical assignments operator:

The Logical OR assignment operator

The logical OR assignment operator ( ||= ) accepts two operands and assigns the right operand to the left operand if the left operand is falsy:

In this syntax, the ||= operator only assigns y to x if x is falsy. For example:

In this example, the title variable is undefined , therefore, it’s falsy. Since the title is falsy, the operator ||= assigns the 'untitled' to the title . The output shows the untitled as expected.

See another example:

In this example, the title is 'JavaScript Awesome' so it is truthy. Therefore, the logical OR assignment operator ( ||= ) doesn’t assign the string 'untitled' to the title variable.

The logical OR assignment operator:

is equivalent to the following statement that uses the logical OR operator :

Like the logical OR operator, the logical OR assignment also short-circuits. It means that the logical OR assignment operator only performs an assignment when the x is falsy.

The following example uses the logical assignment operator to display a default message if the search result element is empty:

The Logical AND assignment operator

The logical AND assignment operator only assigns y to x if x is truthy:

The logical AND assignment operator also short-circuits. It means that

is equivalent to:

The following example uses the logical AND assignment operator to change the last name of a person object if the last name is truthy:

The nullish coalescing assignment operator

The nullish coalescing assignment operator only assigns y to x if x is null or undefined :

It’s equivalent to the following statement that uses the nullish coalescing operator :

The following example uses the nullish coalescing assignment operator to add a missing property to an object:

In this example, the user.nickname is undefined , therefore, it’s nullish. The nullish coalescing assignment operator assigns the string 'anonymous' to the user.nickname property.

The following table illustrates how the logical assignment operators work:

• The logical OR assignment ( x ||= y ) operator only assigns y to x if x is falsy.
• The logical AND assignment ( x &&= y ) operator only assigns y to x if x is truthy.
• The nullish coalescing assignment ( x ??= y ) operator only assigns y to x if x is nullish.

Operators In JavaScript

In this tutorial, you will learn about different types of operators in JavaScript with examples and explanations.

What are Operators in Javascript?

Operators are symbols that defines different kind of oprtations like mathematical operation, logical operation, etc. For example, the symbol of addition (+) tells the javascript engine to add given operators.

These operators with operands (variables or values) are used to perform mathematical operations on the operands. For example, 2 + 3 is a valid javascript expression.

There are many different types of operators in javascript.

• Arithmetic Operators
• Comparison Operators
• Assignment Operators
• Logical Operators
• Bitwise Operators
• Special Operators

1. Arithmetic Operators

Arithmetic operators are used to perform arithmetic operations on javascript variables or values. For example, 2 + 3 , 2 - 3 , 2 * 3 , etc.

Following is the list of arithmetic operators in javascript.

We will be using operands x = 5 and y = 2 in the examples below.

Now let's see some examples of arithmetic operators in javascript.

2. Comparison Operators

Comparison operators are used to compare two values. They return true or false values on the basis of the result.

For example, 2 == 2 , 2 != 2 , 2 < 3 , etc.

Following is the list of comparison operators in javascript.

Now let's see some examples of comparison operators.

3. Assignment Operators

The assignment operator is used to assign or change the value of the operator. For example, a = 10 now a is equal to 10.

In assignment operators can also do arithmetic operations and then assign results to operators. For example, let a = 10; a += 10 now a become 20 as a += 10 is equivalent to a = a + 10 .

Following is the list of assignment operators in javascript. In the following table when a is not defined then consider a = 10 .

Now let's see some examples of assignment operators.

4. Logical Operators

Logical operators perform logical operations in javascript. For example, && operation true && true = true .

Logical operators are also used to combine conditional statements. They are used to combine conditional statements to determine the result of the statement.

The following table lists the logical operators and their results.

Now let's see some examples of logical operators.

5. Bitwise Operators

Bitwise operators are the operators that are used to change the bit values of the operands. Bitwise operators treat their operands as a sequence of 0's and 1's of 32 bits.

These are the following bitwise operators in javascript.

Lets see an example.

6. Special Operators

Special operators serve special purposes. The following operators lie under special operators categories.

These are the following special operators in javascript.

Let's see these operators in brief with an example.

The instanceof operator checks whether the object is an instance of the given constructor.

The typeof operator returns the type of the given object.

The delete operator deletes the given property from the object.

The in operator checks whether the given property is present in the object.

The new operator creates a new object.

The this operator gives the current object.

Ternary Operator ? :

The ? : operator (Ternary Operator) is a conditional operator. It evaluates the first expression and returns the first value. If the first expression is false, it evaluates the second expression and returns the second value.

Javascript Operators

JavaScript includes operators same as other languages. An operator performs some operation on single or multiple operands (data value) and produces a result. For example, in 1 + 2 , the + sign is an operator and 1 is left side operand and 2 is right side operand. The + operator performs the addition of two numeric values and returns a result.

JavaScript includes following categories of operators.

Arithmetic Operators

Comparison operators, logical operators, assignment operators.

• Conditional Operators

Ternary Operator

Arithmetic operators are used to perform mathematical operations between numeric operands.

The following example demonstrates how arithmetic operators perform different tasks on operands.

The ++ and -- operators are unary operators. It works with either left or right operand only. When used with the left operand, e.g., x++ , it will increase the value of x when the program control goes to the next statement. In the same way, when it is used with the right operand, e.g., ++x , it will increase the value of x there only. Therefore, x++ is called post-increment, and ++x is called pre-increment.

String Concatenation

The + operator performs concatenation operation when one of the operands is of string type. The following example demonstrates string concatenation even if one of the operands is a string.

JavaScript provides comparison operators that compare two operands and return a boolean value true or false .

The following example demonstrates the comparison operators.

In JavaScript, the logical operators are used to combine two or more conditions. JavaScript provides the following logical operators.

JavaScript provides the assignment operators to assign values to variables with less key strokes.

JavaScript provides a special operator called ternary operator :? that assigns a value to a variable based on some condition. This is the short form of the if else condition .

The ternary operator starts with conditional expression followed by the ? operator. The second part (after ? and before : ) will be executed if the condition turns out to be true. Suppose, the condition returns false , then the third part (after :) will be executed.

• JavaScript includes operators that perform some operation on single or multiple operands (data value) and produce a result.
• JavaScript includes various categories of operators: Arithmetic operators, Comparison operators, Logical operators, Assignment operators, Conditional operators.
• Ternary operator ?: is a short form of if-else condition.

Specifications

Browser compatibility.

An assignment operator assigns a value to its left operand based on the value of its right operand.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

The basic assignment operator is equal ( = ), which assigns the value of its right operand to its left operand. That is, x = y assigns the value of y to x . The other assignment operators are usually shorthand for standard operations, as shown in the following definitions and examples.

Simple assignment operator is used to assign a value to a variable. The assignment operation evaluates to the assigned value. Chaining the assignment operator is possible in order to assign a single value to multiple variables. See the example.

Addition assignment

The addition assignment operator adds the value of the right operand to a variable and assigns the result to the variable. The types of the two operands determine the behavior of the addition assignment operator. Addition or concatenation is possible. See the addition operator for more details.

Subtraction assignment

The subtraction assignment operator subtracts the value of the right operand from a variable and assigns the result to the variable. See the subtraction operator for more details.

Multiplication assignment

The multiplication assignment operator multiplies a variable by the value of the right operand and assigns the result to the variable. See the multiplication operator for more details.

Division assignment

The division assignment operator divides a variable by the value of the right operand and assigns the result to the variable. See the division operator for more details.

Remainder assignment

The remainder assignment operator divides a variable by the value of the right operand and assigns the remainder to the variable. See the remainder operator for more details.

Exponentiation assignment

The exponentiation assignment operator evaluates to the result of raising first operand to the power second operand. See the exponentiation operator for more details.

Left shift assignment

The left shift assignment operator moves the specified amount of bits to the left and assigns the result to the variable. See the left shift operator for more details.

Right shift assignment

The right shift assignment operator moves the specified amount of bits to the right and assigns the result to the variable. See the right shift operator for more details.

Unsigned right shift assignment

The unsigned right shift assignment operator moves the specified amount of bits to the right and assigns the result to the variable. See the unsigned right shift operator for more details.

Bitwise AND assignment

The bitwise AND assignment operator uses the binary representation of both operands, does a bitwise AND operation on them and assigns the result to the variable. See the bitwise AND operator for more details.

Bitwise XOR assignment

The bitwise XOR assignment operator uses the binary representation of both operands, does a bitwise XOR operation on them and assigns the result to the variable. See the bitwise XOR operator for more details.

Bitwise OR assignment

The bitwise OR assignment operator uses the binary representation of both operands, does a bitwise OR operation on them and assigns the result to the variable. See the bitwise OR operator for more details.

Left operand with another assignment operator

In unusual situations, the assignment operator (e.g. x += y ) is not identical to the meaning expression (here x = x + y ). When the left operand of an assignment operator itself contains an assignment operator, the left operand is evaluated only once. For example:

• Arithmetic operators

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JavaScript Assignment Operators Example

Assignment operator in javascript with example; In this tutorial, you will learn about JavaScript assignment operators with the help of examples. And as well as learn how to assign a value of the right operand to its left operand in js using these assignment operators.

List of JS Assignment Operators

If you want to assign a value of the right(first) operand to its left(second) operand, you can use equal operator in js.

See the example of assignment operator is equal (=):

In this example, Assigned the number 15 to the variable x.

See another example for better understanding:

It’s equivalent to the above example:

JS assignment operator has several shortcuts for performing all the arithmetic operations , which let you assign to the right operand the left operand.

Here, you can see that examples of the following assignment operators:

• += : addition assignment
• -= : subtraction assignment
• *= : multiplication assignment
• /= : division assignment
• %= : remainder assignment
• **= : exponentiation assignment

See the following example:

In this tutorial, you have learned how to use JavaScript assignment operators.

Recommended JavaScript Tutorial

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• DSA with JS - Self Paced
• JS Tutorial
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JS Arithmetic Operators

• Addition(+) Arithmetic Operator in JavaScript
• Subtraction(-) Arithmetic Operator in JavaScript
• Multiplication(*) Arithmetic Operator in JavaScript
• Division(/) Arithmetic Operator in JavaScript
• Modulus(%) Arithmetic Operator in JavaScript
• Exponentiation(**) Arithmetic Operator in JavaScript
• Increment(+ +) Arithmetic Operator in JavaScript
• Decrement(--) Arithmetic Operator in JavaScript
• JavaScript Arithmetic Unary Plus(+) Operator
• JavaScript Arithmetic Unary Negation(-) Operator

JS Assignment Operators

• Addition Assignment (+=) Operator in Javascript
• Subtraction Assignment( -=) Operator in Javascript
• Multiplication Assignment(*=) Operator in JavaScript
• Division Assignment(/=) Operator in JavaScript
• JavaScript Remainder Assignment(%=) Operator
• Exponentiation Assignment(**=) Operator in JavaScript

Left Shift Assignment (<<=) Operator in JavaScript

• Right Shift Assignment(>>=) Operator in JavaScript
• Bitwise AND Assignment (&=) Operator in JavaScript
• Bitwise OR Assignment (|=) Operator in JavaScript
• Bitwise XOR Assignment (^=) Operator in JavaScript
• JavaScript Logical AND assignment (&&=) Operator
• JavaScript Logical OR assignment (||=) Operator
• Nullish Coalescing Assignment (??=) Operator in JavaScript

JS Comparison Operators

• Equality(==) Comparison Operator in JavaScript
• Inequality(!=) Comparison Operator in JavaScript
• Strict Equality(===) Comparison Operator in JavaScript
• Strict Inequality(!==) Comparison Operator in JavaScript
• Greater than(>) Comparison Operator in JavaScript
• Greater Than or Equal(>=) Comparison Operator in JavaScript
• Less Than or Equal(

JS Logical Operators

• NOT(!) Logical Operator inJavaScript
• AND(&&) Logical Operator in JavaScript
• OR(||) Logical Operator in JavaScript

JS Bitwise Operators

• AND(&) Bitwise Operator in JavaScript
• OR(|) Bitwise Operator in JavaScript
• XOR(^) Bitwise Operator in JavaScript
• NOT(~) Bitwise Operator in JavaScript
• Left Shift (
• Right Shift (>>) Bitwise Operator in JavaScript
• Zero Fill Right Shift (>>>) Bitwise Operator in JavaScript

JS Unary Operators

• JavaScript typeof Operator
• JavaScript delete Operator

JS Relational Operators

• JavaScript in Operator
• JavaScript Instanceof Operator

JS Other Operators

• JavaScript String Operators
• JavaScript yield Operator
• JavaScript Pipeline Operator
• JavaScript Grouping Operator

The Left Shift Assignment Operator is represented by “<<=”. This operator moves the specified number of bits to the left and assigns that result to the variable. We can fill the vacated place by 0. The left shift operator treats the integer stored in the variable to the operator’s left as a 32-bit binary number. This can also be explained as the number is shifted to the left by the integer which is the right of the operator and assign the result to the variable.

Where –

• a is the first operand, and
• b is the second operand.

Example 1: In this example, we will see the implementation of the left shift assignment.

Example 2: In this example, we will see left shift operator is not used for the negative number.

Example 3: In this example, we will see the implementation of the left shift assignment operator.

We have a complete list of Javascript Assignment Operators, Please check this article Javascript Assignment Operator .

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