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JavaScript Operator Precedence

Operator precedence describes the order in which operations are performed in an arithmetic expression.

Multiplication (*) and division (/) have higher precedence than addition (+) and subtraction (-).

As in traditional mathematics, multiplication is done first:

let x = 100 + 50 * 3;
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When using parentheses, operations inside the parentheses are computed first:

let x = (100 + 50) * 3;
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Operations with the same precedence (like * and /) are computed from left to right:

let x = 100 / 50 * 3;
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Operator Precedence Values

Expressions in parentheses are computed before the rest of the expression
Function are executed before the result is used in the rest of the expression
Val Operator Description Example
18 ( ) Expression Grouping (100 + 50) * 3
17 . Member Of person.name
17 [] Member Of person["name"]
17 ?. Optional Chaining ES2020 x ?. y
17 () Function Call myFunction()
17 new New with Arguments new Date("June 5,2022")
16 new New without Arguments new Date()
Increment Operators
Posfix increments are executed before prefix increments
15 ++ Postfix Increment i++
15 -- Postfix Decrement i--
14 ++ Prefix Increment ++i
14 -- Prefix Decrement --i
NOT Operators
14 ! Logical NOT !(x==y)
14 ~ Bitwise NOT ~x
Unary Operators
14 + Unary Plus +x
14 - Unary Minus -x
14 typeof Data Type typeof x
14 void Evaluate Void void(0)
14 delete Property Delete delete myCar.color
Arithmetic Operators
Exponentiations are executed before multiplications
Multiplications and divisions are executed before additions and subtractions
13 ** Exponentiation ES2016 10 ** 2
12 * Multiplication 10 * 5
12 / Division 10 / 5
12 % Division Remainder 10 % 5
11 + Addition 10 + 5
11 - Subtraction 10 - 5
11 + Concatenation "John" + "Doe"
Shift Operators
10 << Shift Left x << 2
10 >> Shift Right (signed) x >> 2
10 >>> Shift Right (unsigned) x >>> 2
Relational Operators
9 in Property in Object "PI" in Math
9 instanceof Instance of Object x instanceof Array
Comparison Operators
9 < Less than x < y 
9 <= Less than or equal x <= y
9 > Greater than x > y
9 >= Greater than or equal x >= Array
8 == Equal x == y
8 === Strict equal x === y
8 != Unequal x != y
8 !== Strict unequal x !== y
Bitwise Operators
7 & Bitwise AND x & y
6 ^ Bitwise XOR x ^ y
5 | Bitwise OR x | y
Logical Operators
4 && Logical AND x && y
3 || Logical OR x || y
3 ?? Nullish Coalescing ES2020 x ?? y
Conditional (ternary) Operator
2 ? : Condition ? "yes" : "no"
Assignment Operators
Assignments are executed after other operations
2 = Simple Assignment x + y
2 : Colon Assignment x: 5
2 += Addition Assignment x += y
2 -= Subtraction Assignment x -= y
2 *= Multiplication Assignment x *= y
2 **= Exponentiation Assignment x **= y
2 /= Division Assignment x /= y
2 %= Remainder Assignment x %= y
2 <<= Left Shift Assignment x <<= y
2 >>= Right Shift Assignment x >>= y
2 >>>= Unsigned Right Shift x >>>= y
2 &= Bitwise AND Assignment x &= y
2 |= Bitwise OR Assignment x |= y
2 ^= Bitwise XOR Assignment x ^= y
2 &&= Logical AND Assignment x &= y
2 ||= Logical OR Assignment x ||= y
2 => Arrow x => y
2 yield Pause / Resume yield x
2 yield* Delegate yield* x
2 ... Spread ... x
1 , Comma x , y