How To Make a String Duper Minecraft

Introduction.

If you’re into Minecraft’s technical side, you’ve likely heard about duping glitches. One of the most popular and practical ones is the string duper.

Duping string can save you countless hours of farming spiders or hunting down cobwebs, especially when you’re trying to mass-produce bows, wool, or scaffolding.

In this guide, I’ll walk you through how to create a simple yet effective string duper in Minecraft. Don’t worry if you’re not a redstone genius—I’ll break everything down step-by-step, so you’ll have this trick up and running in no time.

What is a String Duper?

A string duper is essentially a glitch or exploit in Minecraft that lets you duplicate string without going through the usual grind of collecting it.

Normally, you’d get string by killing spiders, breaking cobwebs, or fishing. But with a duper, you can generate infinite string using a few simple game mechanics—especially from certain blocks that interact with string in unintended ways.

This is a useful trick in many survival or creative builds when you need large quantities of string but don’t want to spend days gathering materials.

How Duping Works in Minecraft

Minecraft’s game engine operates under a variety of rules when it comes to physics and item handling. Sometimes, players find ways to exploit those rules—string duping is one such example.

The duplication glitch usually happens by breaking and re-placing blocks under specific conditions, tricking the game into creating more items than it started with.

Let’s dive into the steps on how to set up a string duper.

How Do I Build a String Duper?

Materials You’ll Need:

An End Portal (This duper works near End Portals, so access to the End is crucial)
Coral fans (Dead coral fans are often used to exploit block update detection glitches)
TNT or other items (depending on the method you’re going for, different blocks can be used)

Step-by-Step Instructions

Locate or Create an End Portal: First, you need access to an End Portal. This trick only works when you set up your contraption near one. You don’t need to actually enter the End dimension, but the portal acts as a critical component in the dupe process.
Place Coral Fans: Dead coral fans play an important role in this setup. The glitch that triggers duplication relies on how coral fans interact with the game’s block update mechanics. You’ll need to place the dead coral fans strategically around the End Portal frame.
Exploit Block Update Mechanisms: In Minecraft, certain blocks (like coral fans) can “confuse” the game’s physics engine into thinking an item has been broken multiple times, duplicating it. You’ll exploit this by setting up your redstone system to repeatedly update blocks near the End Portal and the coral fans.
Activate and Collect: Once set up, activating your redstone system will trigger the glitch, duplicating the string. You’ll want to position yourself (or a hopper system) to collect the duplicated string as it generates.

It might take some tinkering to get the setup just right, but once you do, you’ll have an endless supply of string with very minimal effort!

Pros and Cons of Using a String Duper

Pros:

Saves Time: Farming string normally can be a grind. With a string duper, you bypass the need for traditional farming methods entirely, freeing up your time for more important tasks in your world.
Efficient for Large Builds: If you’re working on big projects that require tons of wool, bows, or scaffolding, having an unlimited supply of string at your disposal makes things significantly easier. No more spider farms or exploring for cobwebs!
Easy to Build: String dupers aren’t as complex as some other Minecraft machines, meaning even players with little experience in redstone or technical Minecraft can usually pull it off after some trial and error.
Works in Many Game Versions: Minecraft’s update cycles sometimes patch duping glitches, but string dupers tend to work across multiple versions, especially if you set them up before a patch.

Cons:

Can Feel Cheaty: Depending on how you play Minecraft, using glitches might detract from the challenge or satisfaction of gathering resources manually. Dupers often make the game easier, but you might miss out on the natural progression of resource collection.
Potential for Patch Removal: Mojang often fixes duplication glitches, meaning your setup might become obsolete in future updates. If you’re playing on a server, it’s worth checking if the server allows dupe glitches, as some don’t.
Requires the End Portal: Since this duper relies on an End Portal setup, you’ll need to be fairly advanced in your world to even build one. This method is not viable for early-game players.
Not “Legit” for Some Servers: Many multiplayer servers have strict rules against exploiting game mechanics like duplication glitches. Using a string duper in these environments could lead to getting banned or having your world reset.

Conclusion

Using a string duper in Minecraft can drastically change how you approach resource gathering, particularly for large-scale projects or automation setups. It’s a time-saver, simple to set up, and effective for mass-producing string.

However, there are trade-offs—while it’s incredibly efficient, it might feel like you’re bending the rules of the game a bit too much. It’s up to you to decide whether the convenience is worth it for your playstyle.

Have you tried setting up a string duper in your world? How do you balance using glitches like this with maintaining the challenge of Minecraft?