JavaScript Operators

  

JavaScript Arithmetic Operators

Arithmetic operators are used to perform arithmetic on numbers:

Operator	Description
+	Addition
-	Subtraction
*	Multiplication
**	Exponentiation (ES2016)
/	Division
%	Modulus (Division Remainder)
++	Increment
--	Decrement

   

    <script>

        let a = 100;

        let b = 50;

        let x = a + b;

        // let x = (100 + 50) * a;

        document.write(x);

    </script>

Comparison Operators

Comparison and Logical operators are used to test for true or false.

Comparison operators are used in logical statements to determine equality or difference between variables or values.

 

    <script>

        let x = 5;

        document.write(x == 8);

    </script>

Given that x = 5, the table below explains the comparison operators:

Operator	Description	Comparing	Returns
==	equal to	x == 8	false
		x == 5	true
		x == "5"	true
===	equal value and equal type	x === 5	true
		x === "5"	false
!=	not equal	x != 8	true
!==	not equal value or not equal type	x !== 5	false
		x !== "5"	true
		x !== 8	true
>	greater than	x > 8	false
<	less than	x < 8	true
>=	greater than or equal to	x >= 8	false
<=	less than or equal to	x <= 8	true

JavaScript Assignment Operators

Assignment operators assign values to JavaScript variables.

Operator	Example	Same As
=	x = y	x = y
+=	x += y	x = x + y
-=	x -= y	x = x - y
*=	x *= y	x = x * y
/=	x /= y	x = x / y
%=	x %= y	x = x % y
**=	x **= y	x = x ** y

The addition assignment operator (+=) adds a value to a variable.

   

    <script>

        let x = 5;

        let y = 2;

        let z = x + y;

        document.write(z);

    </script>

   

Logical Operators

Logical operators are used to determine the logic between variables or values.Given that x = 6 and y = 3, the table below explains the logical operators:

        <script>

        let x = 5;

        document.write((x == 5 || y == 5));

    </script>

Operator	Description	Example
&&	and	(x < 10 && y > 1) is true
||	or	(x == 5 || y == 5) is false
!	not	!(x == y) is true

---

JavaScript Operator Precedence Values

Value	Operator	Description	Example
21	( )	Expression grouping	(3 + 4)
20	.	Member	person.name
20	[]	Member	person["name"]
20	()	Function call	myFunction()
20	new	Create	new Date()
18	++	Postfix Increment	i++
18	--	Postfix Decrement	i--
17	++	Prefix Increment	++i
17	--	Prefix Decrement	--i
17	!	Logical not	!(x==y)
17	typeof	Type	typeof x
16	**	Exponentiation (ES2016)	10 ** 2
15	*	Multiplication	10 * 5
15	/	Division	10 / 5
15	%	Division Remainder	10 % 5
14	+	Addition	10 + 5
14	-	Subtraction	10 - 5
13	<<	Shift left	x << 2
13	>>	Shift right	x >> 2
13	>>>	Shift right (unsigned)	x >>> 2
12	<	Less than	x < y
12	<=	Less than or equal	x <= y
12	>	Greater than	x > y
12	>=	Greater than or equal	x >= y
12	in	Property in Object	"PI" in Math
12	instanceof	Instance of Object	instanceof Array
11	==	Equal	x == y
11	===	Strict equal	x === y
11	!=	Unequal	x != y
11	!==	Strict unequal	x !== y
10	&	Bitwise AND	x & y
9	^	Bitwise XOR	x ^ y
8	|	Bitwise OR	x | y
7	&&	Logical AND	x && y
6	||	Logical OR	x || y
5	??	Nullish Coalescing	x ?? y
4	? :	Condition	? "Yes" : "No"
3	+=	Assignment	x += y
3	/=	Assignment	x /= y
3	-=	Assignment	x -= y
3	*=	Assignment	x *= y
3	%=	Assignment	x %= y
3	<<=	Assignment	x <<= y
3	>>=	Assignment	x >>= y
3	>>>=	Assignment	x >>>= y
3	&=	Assignment	x &= y
3	^=	Assignment	x ^= y
3	|=	Assignment	x |= y
2	yield	Pause Function	yield x
1	,	Comma	5 , 6

Expressions in parentheses are fully computed before the value is used in the rest of the expression.