Bitwise AND (&) - JavaScript - MDN Web Docs

The bitwise AND operator ( & ) returns a 1 in each bit position for which the corresponding bits of both operands are 1 s. SkiptomaincontentSkiptosearchSkiptoselectlanguageReferencesJavaScriptJavaScriptExpressionsandoperatorsBitwiseAND(&)ArticleActionsEnglish(US)TryitSyntaxDescriptionExamplesSpecificationsBrowsercompatibilitySeealsoRelatedTopics JavaScript Tutorials: Completebeginners JavaScriptbasics JavaScriptfirststeps JavaScriptbuildingblocks IntroducingJavaScriptobjects JavaScriptGuide Introduction Grammarandtypes Controlflowanderrorhandling Loopsanditeration Functions Expressionsandoperators Numbersanddates Textformatting Regularexpressions Indexedcollections Keyedcollections Workingwithobjects Detailsoftheobjectmodel Usingpromises Iteratorsandgenerators Metaprogramming JavaScriptmodules Intermediate Client-sideJavaScriptframeworks Client-sidewebAPIs Are-introductiontoJavaScript JavaScriptdatastructures Equalitycomparisonsandsameness Closures Advanced Inheritanceandtheprototypechain Strictmode JavaScripttypedarrays MemoryManagement ConcurrencymodelandEventLoop References: Built-inobjects 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Misc JavaScripttechnologiesoverview Lexicalgrammar JavaScriptdatastructures Enumerabilityandownershipofproperties Iterationprotocols Strictmode Transitioningtostrictmode Templateliterals Deprecatedfeatures TryitSyntaxDescriptionExamplesSpecificationsBrowsercompatibilitySeealsoBitwiseAND(&) ThebitwiseANDoperator(&)returnsa1ineachbit positionforwhichthecorrespondingbitsofbothoperandsare1s. TryitSyntaxa&b Description Theoperandsareconvertedto32-bitintegersandexpressedbyaseriesofbits(zeroes andones).Numberswithmorethan32bitsgettheirmostsignificantbitsdiscarded.For example,thefollowingintegerwithmorethan32bitswillbeconvertedtoa32-bit integer: Before:11100110111110100000000000000110000000000001 After:10100000000000000110000000000001 Eachbitinthefirstoperandispairedwiththecorrespondingbitinthesecond operand:firstbittofirstbit,secondbittosecond bit,andsoon. Theoperatorisappliedtoeachpairofbits,andtheresultisconstructedbitwise. ThetruthtablefortheANDoperationis: a b aANDb 0 0 0 0 1 0 1 0 0 1 1 1 .9(base10)=00000000000000000000000000001001(base2) 14(base10)=00000000000000000000000000001110(base2) -------------------------------- 14&9(base10)=00000000000000000000000000001000(base2)=8(base10) BitwiseANDinganynumberxwith0yields 0. ExamplesUsingbitwiseAND//5:00000000000000000000000000000101 //2:00000000000000000000000000000010 5&2;//0 SpecificationsSpecificationECMAScriptLanguageSpecification#prod-BitwiseANDExpressionBrowsercompatibilityBCDtablesonlyloadinthebrowserSeealso BitwiseoperatorsintheJSguide BitwiseANDassignmentoperator Foundaproblemwiththispage?EditonGitHubSourceonGitHubReportaproblemwiththiscontentonGitHubWanttofixtheproblemyourself?SeeourContributionguide.Lastmodified:Apr23,2022,byMDNcontributors