How to Check if an Element Exists in an Array in JavaScript? Last Updated : 07 Nov, 2024 Comments Improve Suggest changes Like Article Like Report Given an array, the task is to check whether an element present in an array or not in JavaScript. If the element present in array, then it returns true, otherwise returns false.The indexOf() method returns the index of first occurance of element in an array, and -1 of the element not found in array.Syntaxlet isExist = array.indexOf(element) !== -1; JavaScript const array = [1, 2, 3, 4, 5]; const element = 3; const isExist = array.indexOf(element) !== -1; console.log(isExist); Outputtrue Please Read JavaScript Array Tutorial for complete understanding of JavaScript Array.Table of ContentUsing includes() MethodUsing find() MethodUsing some() MethodUsing Array findIndex() MethodUsing for Loop (Brute Force Approach)Using includes() MethodThe includes() method returns a boolean value indicating whether an array includes a certain value among its entries or not. JavaScript const array = [1, 2, 3, 4, 5]; const element = 3; let isExist = array.includes( element ); console.log(isExist); Outputtrue Using find() MethodThe find() method returns the value of the first element in the array that satisfies the provided testing function. JavaScript const array = [ 1, 2, 3, 4, 5 ]; const element = 3; let isExist = array.find(item => item === element) !== undefined; console.log( isExist ); Outputtrue Using some() MethodThe some()method tests whether at least one element in the array passes the test condition by the provided function. JavaScript const array = [ 1, 2, 3, 4, 5 ]; const element = 3; const isExist = array.some(item => item === element); console.log(isExist); Outputtrue Using Array findIndex() MethodThe findIndex() method returns the index of the first element in the array that satisfies the provided testing function. Otherwise, it returns -1. JavaScript const array = [ 1, 2, 3, 4, 5 ]; const element = 3; const isExist = array.findIndex(item => item === element) !== -1; console.log(isExist); Outputtrue Using for Loop (Brute Force Approach)This approach iterates over each element of the array and checks if it matches the target element. If a match is found, it returns true; otherwise, it returns false. JavaScript const array = [ 1, 2, 3, 4, 5 ]; const element = 3; let isExist = false; for( let i = 0; i < array.length; i++ ) { if( array[i] === element ) { isExist = true; break; } } console.log(isExist); Outputtrue Comment More infoAdvertise with us Next Article How to Check if an Element Exists in an Array in JavaScript? A amanv09 Follow Improve Article Tags : JavaScript Web Technologies JavaScript-QnA WebTech-FAQs Similar Reads JavaScript Tutorial JavaScript is a programming language used to create dynamic content for websites. It is a lightweight, cross-platform, and single-threaded programming language. 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