Creating a datapack

Steps

Step 1: Setting up a folder

The first step to creating a Datapack is setting up a folder for the datapack. This will be the root folder of your Datapack which houses all the files. You can name the folder whatever you want so for this tutorial we'll be naming it My Datapack.

Step 2: Add pack.mcmeta

Inside your folder you just created create a text file called pack.mcmeta. This file is crucial as it holds the description of your datapack and specifies which Minecraft version it supports (pack format). An example for the contents of the text file is as followed:

{
    "pack": {
      "description": "My Dirt To Diamond recipe",
      "pack_format": 15
    }
}

NOTE

A list of which Minecraft version corresponds to which pack_format can be found here.

TIP

From 1.20.2 onwards you can specify a range of pack formats using the optional supported_formats field.
Examples: 18, [18,19], {"min_inclusive": 18, "max_inclusive": 19}

Supported Formats example

{
    "pack": {
      "description": "My Dirt To Diamond recipe",
      "pack_format": 18,
      "supported_formats": {
        "min_inclusive": 18,
        "max_inclusive": 19
      }
    }
}

Step 3: Add the data folder

In the same folder as your pack.mcmeta needs to be a folder with the name data. This data folder will house your recipes, advancements, worldgen etc. In the end, you should end up with the following folder structure

Step 4: Add your desired change

Now you're ready to add your desired change to the datapack. For this example, we'll add a simple recipe that turns dirt to diamonds. To do this I'll create a folder inside of the data folder with the namespace I want my recipe to be under.

Note: You should use a unique namespace to avoid conflicts between different datapacks (or mods) unless you're overriding.

If you are overriding a vanilla recipe we would create a folder with the namespace minecraft.

For this example I'll be creating a folder called mydatapack in which I'll create a folder called recipes which is the namespace the game reads recipes from. Note: You can find a list of vanilla namespaces here

In the created recipes folder I'll create a text file called dirt_to_diamond.json with the following contents:

{
  "type": "minecraft:crafting_shapeless",
  "ingredients": [
    {
      "item": "minecraft:dirt"
    }
  ],
  "result": {
    "item": "minecraft:diamond"
  }
}

After this step, my folder structure is as follows:

Step 4: Zip it up

Now it's time to go back to the root of the datapack you created. Once in the root of the folder put both pack.mcmeta and data in a zip and name it.

On Windows you select the file and folder -> Right-click what you selected and click Send to and select Compressed (zipped) folder and then name the zip whatever you want to name the datapack.

(If using WinRAR you can select the files -> Right-click -> press Add to archive -> name it -> Make sure the .zip format is selected and press OK.

NOTE

I only have experience with Windows, so if using MacOS or Linux I do not currently know how to create a zip. Feel free to tell me and I'll add a section for them.

Closing

If you followed along you've successfully created a Datapack that adds a recipe that allows you to turn a piece of dirt into a diamond.

For information on how to add the datapack to your world see the tutorial on adding.