JavaScript Operators

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

2 + 3;  // 5

Here, we used the + operator to add the operands 2 and 3.

JavaScript Operator Types

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

1. Arithmetic Operators
2. Assignment Operators
3. Comparison Operators
4. Logical Operators
5. Bitwise Operators
6. String Operators
7. Miscellaneous Operators

1. JavaScript Arithmetic Operators

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

5 - 3;  // 2

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

Commonly Used Arithmetic Operators

Example 1: Arithmetic Operators in JavaScript

let x = 5;

// addition operator
console.log("Addition: x + 3 = ", x + 3);

// subtraction operator
console.log("Subtraction: x - 3 =", x - 3);

// multiplication operator
console.log("Multiplication: x * 3 =", x * 3);

// division operator
console.log("Division: x / 3 =", x / 3);

// remainder operator
console.log("Remainder: x % 3 =", x % 3);

// increment operator
console.log("Increment: ++x =", ++x);

// decrement operator
console.log("Decrement: --x =", --x);

// exponentiation operator
console.log("Exponentiation: x ** 3 =", x ** 3);

Output

Addition: x + 3 =  8
Subtraction: x - 3 = 2
Multiplication: x * 3 = 15
Division: x / 3 = 1.6666666666666667
Remainder: x % 3 = 2
Increment: ++x = 6
Decrement: --x = 5
Exponentiation: x ** 3 = 125

2. JavaScript Assignment Operators

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

let x = 5;

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

Commonly Used Assignment Operators

Example 2: Assignment Operators in JavaScript

// assignment operator
let a = 7;
console.log("Assignment: a = 7, a =", a);

// addition assignment operator
a += 5;  // a = a + 5
console.log("Addition Assignment: a += 5, a =", a);

// subtraction assignment operator
a -= 5;  // a = a - 5
console.log("Subtraction Assignment: a -= 5, a =", a);

// multiplication assignment operator
a *= 2;  // a = a * 2
console.log("Multiplication Assignment: a *= 2, a =", a);

// division assignment operator
a /= 2;  // a = a / 2
console.log("Division Assignment: a /= 2, a =", a);

// remainder assignment operator
a %= 2;  // a = a % 2
console.log("Remainder Assignment: a %= 2, a =", a);

// exponentiation assignment operator
a **= 2;  // a = a**2
console.log("Exponentiation Assignment: a **= 7, a =", a);

Output

Assignment: a = 7, a = 7
Addition Assignment: a += 5, a = 12
Subtraction Assignment: a -= 5, a = 7
Multiplication Assignment: a *= 2, a = 14
Division Assignment: a /= 2, a = 7
Remainder Assignment: a %= 2, a = 1
Exponentiation Assignment: a **= 7, a = 1

3. JavaScript Comparison Operators

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

const a = 3, b = 2;
console.log(a > b);

// Output: true 

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.

Note: In the above example, a > b is called a boolean expression since evaluating it results in a boolean value.

Commonly Used Comparison Operators

Example 3: Comparison Operators in JavaScript

// equal to operator
console.log("Equal to: 2 == 2 is", 2 == 2);

// not equal operator
console.log("Not equal to: 3 != 3 is", 3 != 3);

// strictly equal to operator
console.log("Strictly equal to: 2 === '2' is", 2 === '2');

// strictly not equal to operator
console.log("Strictly not equal to: 2 !== '2' is", 2 !== '2');

// greater than operator
console.log("Greater than: 3 > 3 is", 3 > 3);

// less than operator
console.log("Less than: 2 > 2 is", 2 > 2);

// greater than or equal to operator
console.log("Greater than or equal to: 3 >= 3 is", 3 >= 3);

// less than or equal to operator
console.log("Less than or equal to: 2 <= 2 is", 2 <= 2);

Output

Equal to: 2 == 2 is true
Not equal to: 3 != 3 is false
Strictly equal to: 2 === '2' is false
Strictly not equal to: 2 !== '2' is true
Greater than: 3 > 3 is false
Less than: 2 > 2 is false
Greater than or equal to: 3 >= 3 is true
Less than or equal to: 2 <= 2 is true

console.log(3 == "3");  // true

console.log(4 === "4");  // false

4. JavaScript Logical Operators

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

const x = 5, y = 3;
console.log((x < 6) && (y < 5));

// Output: true

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 4: Logical Operators in JavaScript

let x = 3;

// logical AND
console.log((x < 5) && (x > 0));  // true
console.log((x < 5) && (x > 6));  // false

// logical OR
console.log((x > 2) || (x > 5));  // true
console.log((x > 3) || (x < 0));  // false

// logical NOT
console.log(!(x == 3));  // false
console.log(!(x < 2));  // true

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

let str1 = "Hel", str2 = "lo";
console.log(str1 + str2);

// Output: Hello

Also Read:

• JavaScript Spread Operator
• JavaScript Ternary Operator
• JavaScript typeof Operator