Deprecated features ](/en-US/docs/Web/JavaScript/Reference/Deprecated_and_obsolete_features)

##  In this article

  * Try it 
  * Syntax 
  * Description 
  * Examples 
  * Specifications 
  * Browser compatibility 
  * See also 

#  Bitwise OR assignment (|=)

The **bitwise OR assignment (` |= ` ) ** operator performs [ bitwise OR ](/en-
US/docs/Web/JavaScript/Reference/Operators/Bitwise_OR) on the two operands and
assigns the result to the left operand.

##  Try it

##  Syntax

js

    
    
    x |= y
    

##  Description

` x |= y ` is equivalent to ` x = x | y ` , except that the expression ` x ` is only evaluated once. 

##  Examples

###  Using bitwise OR assignment

js

    
    
    let a = 5;
    a |= 2; // 7
    // 5: 00000000000000000000000000000101
    // 2: 00000000000000000000000000000010
    // -----------------------------------
    // 7: 00000000000000000000000000000111
    
    let b = 5n;
    b |= 2n; // 7n
    

##  Specifications

Specification  
---  
[ ECMAScript Language Specification  
#  sec-assignment-operators  ](https://tc39.es/ecma262/multipage/ecmascript-
language-expressions.html#sec-assignment-operators)  
  
##  Browser compatibility

BCD tables only load in the browser  with JavaScript enabled. Enable
JavaScript to view data.

##  See also

  * [ Assignment operators in the JS guide ](/en-US/docs/Web/JavaScript/Guide/Expressions_and_operators#assignment_operators)
  * [ Bitwise OR ( ` | ` ) ](/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_OR)
  * [ Logical OR assignment ( ` ||= ` ) ](/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR_assignment)

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