RemapIDs

RemapIDs redirects one registry ID to another using plain JSON files. Removed a mod from your modpack? Point its blocks and items at replacements from another mod and existing worlds keep working. No code, no world editing, no datapack surgery.

Getting Started Install the mod and write your first remap in five minutes.

Remap File Reference Every field, every remap type, wildcards, and tags.

Examples Copy-paste solutions for common modpack situations.

Advanced Chain resolution, pre-1.13 numerical IDs, and how it works under the hood.

Troubleshooting Verify remaps in game and decode log warnings.

Supported versions

MC 1.20.1: Forge MC 1.20.1: Fabric MC 1.21.1: NeoForge MC 1.21.1: Fabric

No dependencies beyond the loader itself. Fabric API is not required.

What it solves

Removed a mod from your pack. Remap its block and item IDs to equivalents from another mod so existing worlds don’t lose placed blocks or stored items.
Duplicate materials everywhere. Five mods each add a silver ingot. Redirect four of them to the fifth, across recipes, loot tables, and tags, and your pack behaves like there was only ever one.
Replacing vanilla content. Remap vanilla blocks and items to modded equivalents. Copper blocks become brass blocks, everywhere.
Ancient worlds. Migrating a pre-1.13 world? Numerical IDs like 35:14 work as remap sources and resolve through a built-in flattening table.

A taste

One file in config/remapids/remaps/, one entry:

{
  "remaps": [
    {
      "source": "iceandfire:silver_ingot",
      "target": "othermod:silver_ingot"
    }
  ]
}

Restart the game. Every iceandfire:silver_ingot in player inventories, chests, recipes, loot tables, and tags now resolves to othermod:silver_ingot. When no types filter is given, RemapIDs applies the remap everywhere it makes sense.

Head to Getting Started for the full walkthrough.