Left Shift Assignment (<<=) Operator in JavaScript Last Updated : 23 Jul, 2025 Comments Improve Suggest changes Like Article Like Report The Left Shift Assignment Operator is represented by "<<=". This operator moves the specified number of bits to the left and assigns that result to the variable. We can fill the vacated place by 0. The left shift operator treats the integer stored in the variable to the operator's left as a 32-bit binary number. This can also be explained as the number is shifted to the left by the integer which is the right of the operator and assign the result to the variable. Syntax a <<= b Or a = a << b Where - a is the first operand, andb is the second operand. Example 1: In this example, we will see the implementation of the left shift assignment. JavaScript let x = 7; // 00000000000000000000000000000111 x <<= 2; // 00000000000000000000000000011100 console.log(x); Output28 Example 2: In this example, we will see left shift operator is not used for the negative number. JavaScript let x = 1; // 00000000000000000000000000000001 x <<= -1; // -10000000000000000000000000000000 console.log(x); Output-2147483648 Example 3: In this example, we will see the implementation of the left shift assignment operator. JavaScript let a = 10; // 00000000000000000000000000001010 let b = 5 // 00000000000000000000000000000101 a = a << b; // 00000000000000000000000101000000 console.log(a); Output320 We have a complete list of Javascript Assignment Operators, Please check this article Javascript Assignment Operator. Supported Browser: Chrome 1Edge 12Firefox 1Opera 3Safari 1 Comment More info M mansigeekso9ii Follow Improve Article Tags : JavaScript Web Technologies Explore JavaScript BasicsIntroduction to JavaScript4 min readVariables and Datatypes in JavaScript6 min readJavaScript Operators5 min readControl Statements in JavaScript4 min readArray & StringJavaScript Arrays7 min readJavaScript Array Methods7 min readJavaScript Strings5 min readJavaScript String Methods9 min readFunction & ObjectFunctions in JavaScript5 min readJavaScript Function Expression3 min readFunction Overloading in JavaScript4 min readObjects in JavaScript4 min readJavaScript Object Constructors4 min readOOPObject Oriented Programming in JavaScript3 min readClasses and Objects in JavaScript4 min readWhat Are Access Modifiers In JavaScript ?5 min readJavaScript Constructor Method7 min readAsynchronous JavaScriptAsynchronous JavaScript2 min readJavaScript Callbacks4 min readJavaScript Promise4 min readEvent Loop in JavaScript4 min readAsync and Await in JavaScript2 min readException HandlingJavascript Error and Exceptional Handling6 min readJavaScript Errors Throw and Try to Catch2 min readHow to create custom errors in JavaScript ?2 min readJavaScript TypeError - Invalid Array.prototype.sort argument1 min readDOMHTML DOM (Document Object Model)9 min readHow to select DOM Elements in JavaScript ?3 min readJavaScript Custom Events4 min readJavaScript addEventListener() with Examples9 min readAdvanced TopicsClosure in JavaScript4 min readJavaScript Hoisting6 min readScope of Variables in JavaScript3 min readJavaScript Higher Order Functions7 min readDebugging in JavaScript4 min read Like