C Operator Precedence

The following table lists the precedence and associativity of C operators. Operators are listed top to bottom, in descending precedence.

Precedence	Operator	Description	Associativity
1	++ --	Suffix/postfix increment and decrement	Left-to-right
	()	Function call
	[]	Array subscripting
	.	Structure and union member access
	->	Structure and union member access through pointer
	(type){list}	Compound literal(C99)
2	++ --	Prefix increment and decrement	Right-to-left
	+ -	Unary plus and minus
	! ~	Logical NOT and bitwise NOT
	(type)	Type cast
	*	Indirection (dereference)
	&	Address-of
	sizeof	Size-of
	_Alignof	Alignment requirement(C11)
3	* / %	Multiplication, division, and remainder	Left-to-right
4	+ -	Addition and subtraction
5	<< >>	Bitwise left shift and right shift
6	< <=	For relational operators < and ≤ respectively
	> >=	For relational operators > and ≥ respectively
7	== !=	For relational = and ≠ respectively
8	&	Bitwise AND
9	^	Bitwise XOR (exclusive or)
10	|	Bitwise OR (inclusive or)
11	&&	Logical AND
12	||	Logical OR
13[note 1]	?:	Ternary conditional[note 2]	Right-to-Left
14	=	Simple assignment
	+= -=	Assignment by sum and difference
	*= /= %=	Assignment by product, quotient, and remainder
	<<= >>=	Assignment by bitwise left shift and right shift
	&= ^= |=	Assignment by bitwise AND, XOR, and OR
15	,	Comma	Left-to-right

1. Fictional precedence level, see Notes below
2. The expression in the middle of the conditional operator (between ? and :) is parsed as if parenthesized: its precedence relative to ?: is ignored.

When parsing an expression, an operator which is listed on some row will be bound tighter (as if by parentheses) to its arguments than any operator that is listed on a row further below it. For example, the expression *p++ is parsed as *(p++), and not as (*p)++.

Operators that are in the same cell (there may be several rows of operators listed in a cell) are evaluated with the same precedence, in the given direction. For example, the expression a=b=c is parsed as a=(b=c), and not as (a=b)=c because of right-to-left associativity.

Notes

Precedence and associativity are independent from order of evaluation.

The C language standard doesn't specify operator precedence. It specifies the language grammar, and the precedence table is derived from it to simplify understanding. There is a part of the grammar that cannot be represented by a precedence table: an assignment-expression is not allowed as the right hand operand of a conditional operator, so e = a < d ? a++ : a = d is an expression that cannot be parsed, and therefore relative precedence of conditional and assignment operators cannot be described easily.

However, many C compilers use non-standard expression grammar where ?: is designated higher precedence than =, which parses that expression as e = ( ((a < d) ? (a++) : a) = d ), which then fails to compile due to semantic constraints: ?: is never lvalue and = requires a modifiable lvalue on the left. This is the table presented on this page.

Note that this is different in C++, where the conditional operator has the same precedence as assignment.

Associativity specification is redundant for unary operators and is only shown for completeness: unary prefix operators always associate right-to-left (sizeof ++*p is sizeof(++(*p))) and unary postfix operators always associate left-to-right (a[1][2]++ is ((a[1])[2])++). Note that the associativity is meaningful for member access operators, even though they are grouped with unary postfix operators: a.b++ is parsed (a.b)++ and not a.(b++).

References

• C11 standard (ISO/IEC 9899:2011):
• A.2.1 Expressions
• C99 standard (ISO/IEC 9899:1999):
• A.2.1 Expressions
• C89/C90 standard (ISO/IEC 9899:1990):
• A.1.2.1 Expressions

See Also

Order of evaluation of operator arguments at run time.

Common operators
assignment	increment decrement	arithmetic	logical	comparison	member access	other
a = b a += b a -= b a *= b a /= b a %= b a &= b a |= b a ^= b a <<= b a >>= b.	++a --a a++ a--	+a -a a + b a - b a * b a / b a % b ~a a & b a | b a ^ b a << b a >> b.	!a a && b a || b.	a == b a != b a < b a > b a <= b a >= b.	a[b] *a &a a->b a.b.	a(...) a, b (type) a ? : sizeof _Alignof (since C11).

C++ documentation for C++ operator precedence