ItemDuper-Pro
by VoidOJ
ItemDuper-Pro lets a player press one key to double the item held in the main hand, with a default G key that can be rebound.
What it does
Holding an item in the main hand and pressing the trigger key doubles it at once, and repeated presses keep doubling the stack from 1 to 2, 4, 8 up to 2,048 items per stack. The mod widens the stack limit for the duplicated items and handles full inventories without losing what is moved or placed.
The duplication is synchronized from the server side, so the result persists when items are moved or placed. In survival worlds and on multiplayer servers alike, ItemDuper-Pro runs as a rebuilt, improved take on the earlier DupeTrigger mod from AstraLucid, according to its author. Cheats are needed to use it on the cheat-restricted settings of a world, which the author notes as a requirement.
The mod is a Fabric mod for 1.21.6 and 1.21.7, released under All rights reserved, so the code is not open source. Client and server both need it, and it is categorized under Optimization, with Cursed and Game mechanics as secondary tags.
Key features
One-key duplication
A single key doubles the item in the main hand, so no command or menu is needed for each duplication.
Rebindable trigger
The default G key can be changed to any other key in the controls settings.
Enhanced stack limits
Duplicated items can reach up to 2,048 per stack, well beyond the usual vanilla stack size.
Server-side synchronization
Duplication results are synchronized from the server, so the outcome stays consistent for every player.
Inventory handling
Full inventories are handled without losing items, so a duplication that does not fit is managed safely.
Gallery
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Survival and multiplayer play
The mod works in survival mode and on multiplayer servers, where its duplication is synchronized across players.
Who it’s for: Players who run the mod for item duplication in cheat-enabled worlds, and server owners who want the duplication synchronized for all players on their server.
Questions
Does ItemDuper-Pro need Fabric API?
Does the server need ItemDuper-Pro?
Can the trigger key be changed?
In the catalog
ItemDuper-Pro is one of 3,545 Optimization mods on ModsFinder, and one of 2,575 Optimization mods for Fabric. 13,697 mods support Minecraft 1.21.7.
Similar mods
What the author says
A recreated and enhanced version of the original DupeTrigger mod by AstraLucid
Official listing
- Modrinth page
- modrinth.com/mod/itemduper-pro
- Owner
- VoidOJ
- Published
- 2025-06-18
- Updated on Modrinth
- 2025-07-05
- Facts verified
- 2026-10-15