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CurseForge · Minecraft mod
Duper
A lightweight dupe mod with a simple keybind.
Choose a version Pick your version below, then grab the matching file.
Quick answer
Which Duper release matches 1.20 Forge?
Best match for your filters duper-forge-0.20.1.jar
Game version 1.20.1, 1.20
Loader Forge
duper-forge-0.20.1.jar targets 1.20.1, 1.20 with Forge. The project page does not say whether this file belongs on the client, dedicated server, or both. No extra mods listed for this file.
Where it goes
Is Duper required on the client, server, or both?
The project page does not say whether this file belongs on the client, dedicated server, or both.
Client Source doesn’t say
Dedicated server Source doesn’t say
Loader for this release Forge
Required install it here Optional supported, not mandatory Not supported do not install here Source doesn’t say do not assume
The source does not explicitly classify this release as client-only or server-only.
What else does duper-forge-0.20.1.jar need?
duper-forge-0.20.1.jar on 1.20 Forge. Every mod below is checked against that same setup.
This file does not list any required mods. Do not add a library just because a different file uses it.
This file does not list any required or optional mods.
Before you install it
Add Duper without breaking your instance.
Built for duper-forge-0.20.1.jar on 1.20 Forge. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use duper-forge-0.20.1.jar. It targets 1.20.1, 1.20 with Forge; another release may have different loader, side or dependency requirements.
- 02
Bring the mods it needs
This file does not list any required mods. Do not add a library just because a different file uses it.
- 03
Put it on the correct side
The project page does not say whether this file belongs on the client, dedicated server, or both.
- 04
Pick the file you checked
Use the “Get this file” button beside duper-forge-0.20.1.jar. It opens that exact file at the source.
About this project
What does Duper add?
This mod was made together with ChatGPT, Copilot.
-Lightweight and simple - no commands needed.
-Press the "=" key (default, can be changed in Controls) to duplicate the item in your main hand.
-Works in both singleplayer and multiplayer servers (the server must also have the mod installed).
Project description from CurseForge.
Pick your setup
Duper by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
Minecraft version
26.2
2 loader buildsMinecraft version
26.1.2
2 loader buildsMinecraft version
26.1.1
2 loader buildsMinecraft version
26.1
2 loader buildsMinecraft version
1.21.11
2 loader buildsMinecraft version
1.21.10
2 loader buildsMinecraft version
1.21.9
2 loader buildsMinecraft version
1.21.8
2 loader buildsMinecraft version
1.21.7
2 loader buildsMinecraft version
1.21.6
2 loader buildsMinecraft version
1.21.5
2 loader buildsShowing the newest 12 of 18 game versions. Older files are in the list below.
Check the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
Duper versions and loaders
duper-forge-0.20.1.jar
13 May 2026
Client Source doesn’t say Server Source doesn’t say Dependencies No extras listed Listed on Release listing
Check the 1.20 · Forge setup 1.20.1Forge1.20 release
Looking for an older file? The official CurseForge project page is in Resources.
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