World's simplest browser-based utility for duplicating list items. Input your list and specify duplication criteria to create copies of items. Perfect for data expansion, testing, or creating repeated patterns.
This tool allows you to duplicate items in a list. You can specify the number of copies (including fractional values), control whether items are concatenated or interweaved, and even reverse the duplicated items. It's useful for creating repeated patterns, generating test data, or expanding lists with predictable content.
This example shows how to duplicate a list of words.
Hello World
Hello World Hello World
This example shows how to duplicate a list in reverse order.
Hello World
Hello World World Hello
This example shows how to interweave items instead of concatenating them.
Hello World
Hello Hello World World
This example shows how to duplicate a list with a fractional number of copies.
apple banana cherry
apple banana cherry apple banana
Sort list items in specified order
Unwrap list items from structured format
Quickly reverse a list
Find unique items in a list
Find most frequently occurring items
Split a list into fixed-size chunks
Wrap list items with specified criteria
Rotate list items by specified positions
Randomize the order of list items
Truncate list to specified number of items