Minecraft:Data version

Template:Exclusive

A data version, also known as a world version,<ref>server.jar or javabridge library source, located in class com.mojang.bridge.game.GameVersion</ref><ref>As appeared in the version.json format.</ref> is a positive integer used in a world saved data to denote a specific version, and determines whether the player should be warned about opening that world due to client version incompatibilities.

Usage

File:Outdated singleplayer world.png

The game prompting the player whether they want to back up their outdated world.

Upon selecting and loading a Minecraft:singleplayer world, the game checks if the client has a data version newer or older than the selected world. If it does, the game then prompts the user whether they want to back up their world before playing it if the world is older, or warn them that their world may become corrupted if the world is newer.

Versioning

Every version of Java Edition since Minecraft:15w32a, including minor releases and snapshots, has its own data version. The version takes the form of an ever-increasing positive integer unlike client versions. Data versions are necessary because client versions usually cannot be directly compared since they use different formats (i.e., "1.14" and "19w02a" cannot be compared). Data versions may skip many numbers between any release (to leave space for hotfixes), and may be incremented by a non-single amount for a new version.

Storage locations

Data versions can be found in many different places.

Player data

In-game, the data version can be obtained using the command Template:Cmd.

Version command

In Minecraft:Java Edition 25w15a and later, running Template:Cmd prints the data version to chat.

`options.txt`

The first line of Minecraft:options.txt since Minecraft:1.10-pre1 displays the data version, named version.

`.dat` and `.nbt` files

All .dat and .nbt files contain the data version in their root compound of when the file was last saved.

Template:Nbt
- Template:Nbt: An integer displaying the data version.

`level.dat`

The data version is stored in two places inside the level.dat file of a world save: in the root Template:Cd compound named Template:Cd and also in the Template:Cd compound named Template:Cd.

Template:Nbt level.dat
- Template:Nbt: Information about the level.dat file.
  - Template:Nbt: An integer displaying the data version.
  - Template:Nbt: Versioning information about when the world was last saved.
    - Template:Nbt: An integer displaying the data version.

Region files

Each chunk in the region files (located in Minecraft:.minecraft\saves\<world name>\region named r.<region X>.<region Z>.mca) contains information about the data version when it was last saved.

Template:Nbt: Information about the region at exact region coordinates [x,y] (1 region = 32×32 chunks)
- Template:Nbt: Information about the chunk at relative chunk coordinates [x₁,y₁], located at exact chunk coordinates [x₂,y₂] (1 chunk = 16×16 blocks)
  - Template:Nbt: An integer displaying the data version.

`version.json`

Each Minecraft build since Minecraft:18w47b also specifies its current data version in the Minecraft:version.json file, found in the root directory of the client and server jars.