JavaScript Array indexOf() Method Last Updated : 27 Sep, 2024 Comments Improve Suggest changes Like Article Like Report The indexOf() method in JavaScript is used to find the position of the first occurrence of a specific value in an array. If the value is not present, it returns -1. This method is handy for quickly determining where a particular item is located within an array.Syntax:array.indexOf(element, start)Parameters:element: This parameter holds the element whose index will be returned.start: This parameter is optional and holds the starting point of the array, where the default value is 0 to begin the search.Return value:The method returns the index of the first occurrence of the specified element.If the element is not found, it returns -1.Example 1: Finding Index of Element in ArrayThis code demonstrates the use of the indexOf() method to find the index of the element "gfg" in the array name. The index of "gfg" is stored in the variable a and then logged into the console. JavaScript let name = ['gfg', 'cse', 'geeks', 'portal']; a = name.indexOf('gfg') // Printing result of method console.log(a) Output0 Example 2: Searching Element in ArrayThis code demonstrates the use of the indexOf() method to find the index of a specific element (2) in an array (A). It returns the index of the first occurrence of the element in the array (1 in this case). If the element is not found, it returns -1. JavaScript // Taking input as an array A // having some elements. let A = [1, 2, 3, 4, 5]; // indexOf() method is called to // test whether the searching element // is present in given array or not. a = A.indexOf(2) // Printing result of method. console.log(a); Output1 We have a complete list of Javascript Array methods, to check those please go through this Javascript Array Complete reference article.Supported Browsers: Google ChromeEdge FirefoxOperaSafari Comment More infoAdvertise with us Next Article JavaScript Array indexOf() Method H HGaur Follow Improve Article Tags : Misc JavaScript Web Technologies javascript-array Practice Tags : Misc Similar Reads JavaScript Array() Constructor The Array() constructor is used to create Array objects and the array constructor can be called with or without a new keyword, both can create a new Array.Syntax:new Array(Value1, Value2, ...);new Array(ArrayLength);Array(Value1, Value2, ...);Array(ArrayLength);Parameters: ValueN: An array initializ 2 min read JavaScript Array constructor Property The JavaScript Array constructor property is used to return the constructor function for an array object. 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