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The bitwise AND assignment operator (&=) uses the binary representation of both operands, does a bitwise AND operation on them and assigns the result to the variable.

Syntax

Operator: x &= y
Meaning:  x  = x & y

Examples

Using bitwise AND assignment

let a = 5;
// 5:     00000000000000000000000000000101
// 2:     00000000000000000000000000000010
a &= 2; // 0

Specifications

Specification
ECMAScript (ECMA-262)
The definition of 'Assignment operators' in that specification.

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
Bitwise AND assignment (x &= y)Chrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 3Opera Full support 3Safari Full support 1WebView Android Full support 1Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support 10.1Safari iOS Full support 1Samsung Internet Android Full support 1.0nodejs Full support 0.1.100

Legend

Full support  
Full support

See also

Document Tags and Contributors

Contributors to this page: fscholz
Last updated by: fscholz,