JavaScript Program to Reverse a Linked List Last Updated : 23 Jul, 2025 Comments Improve Suggest changes Like Article Like Report A linked list is a data structure where elements are stored in nodes, and each node points to the next node in the sequence. Reversing a linked list involves changing the direction of the pointers, making the last node the new head and the head the new tail. Below are the approaches to reverse a linked list in JavaScript: Table of Content Reversing a Linked List Using Iteration Reversing a Linked List Using RecursionReversing a Linked List Using Iteration We will use a loop to iterate through the elements and the pointer nodes of the linked list and change the next pointers of each node in such a way that their order is reversed. Example: The below code iteratively reverses the linked list in JavaScript. JavaScript class Node { constructor(data, next = null) { this.data = data; this.next = next; } } class LinkedList { constructor() { this.head = null; } insertFirst(data) { this.head = new Node(data, this.head); } printList() { let current = this.head; while (current !== null) { console.log(current.data); current = current.next; } } reverse() { let prev = null; let current = this.head; let next = null; while (current !== null) { next = current.next; current.next = prev; prev = current; current = next; } this.head = prev; } } const linkedList = new LinkedList(); linkedList.insertFirst(3); linkedList.insertFirst(2); linkedList.insertFirst(1); console.log("Original Linked List:"); linkedList.printList(); linkedList.reverse(); console.log("\nReversed Linked List:"); linkedList.printList(); OutputOriginal Linked List: 1 2 3 Reversed Linked List: 3 2 1 Time Complexity: O(N) Space Complexity: O(1) Reversing a Linked List Using RecursionRecursion is a process in which a function calls itself directly or indirectly. We are going to reverse the linked list by iterating through its elements using recursion and change their node values. Example: The below code is the implementation of the recursive approach to reverse the linked list in JavaScript. JavaScript class Node { constructor(data, next = null) { this.data = data; this.next = next; } } class LinkedList { constructor() { this.head = null; } insertFirst(data) { this.head = new Node(data, this.head); } reverseRecursiveUtil(current, prev) { if (current === null) { this.head = prev; return; } const next = current.next; current.next = prev; this.reverseRecursiveUtil(next, current); } reverseRecursive() { this.reverseRecursiveUtil(this.head, null); } printList() { let current = this.head; while (current !== null) { console.log(current.data); current = current.next; } } } const linkedList = new LinkedList(); linkedList.insertFirst(3); linkedList.insertFirst(2); linkedList.insertFirst(1); console.log("Original Linked List:"); linkedList.printList(); linkedList.reverseRecursive(); console.log("\nReversed Linked List:"); linkedList.printList(); OutputOriginal Linked List: 1 2 3 Reversed Linked List: 3 2 1 Time Complexity: O(N) Space Complexity: O(N) Reverse a linked list iteratively in JavaScript Visit Course Comment More infoAdvertise with us R rajmohit7114 Follow Improve Article Tags : JavaScript Web Technologies JavaScript-Program Similar Reads Learn Data Structures with Javascript | DSA using JavaScript Tutorial JavaScript (JS) is the most popular lightweight, interpreted programming language, and might be your first preference for Client-side as well as Server-side developments. 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