JavaScript - Replace an Item from JS Array Last Updated : 12 Jul, 2025 Comments Improve Suggest changes Like Article Like Report These are the following ways to replace an item from the JS array: 1. Using Array IndexingThe Array Indexing approach replaces an item in an array by directly accessing its position using the index and assigning a new value. This method is straightforward, modifies the original array, and is ideal for known index positions. JavaScript let arr = [1, 2, 3, 4, 5]; const idx = 2; const val = 10; arr[idx] = val; console.log(arr); Output[ 1, 2, 10, 4, 5 ] 2. Using the splice() MethodThe splice() method in JavaScript is another way to replace items in an array. This method allows you to remove items and insert new ones at the specified position in the array.Note: Splice() method deletes zero or more elements of an array starting with including the start_index element and replaces those elements with zero or more elements specified in the argument list. JavaScript let arr = [10, 20, 30]; arr.splice(1, 1, 25); console.log(arr); Output[ 10, 25, 30 ] 3. Using the indexOf() MethodUsing the indexOf() method finds the index of an element in an array, allowing you to perform operations based on its presence or absence. JavaScript const arr = ['a', 'b', 'c']; const idx = arr.indexOf('a'); if (idx !== -1) { arr[idx] = 'z'; } console.log(arr); Output[ 'z', 'b', 'c' ] Comment More info A akshatyadav Follow Improve Article Tags : JavaScript Web Technologies javascript-array JavaScript-DSA 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