Pack format

Pack format, sometimes referred to as pack version, is a number used in pack.mcmeta to describe what Java Edition versions a resource pack or data pack is compatible with. Each version specifies the pack formats it supports in its version.json. The pack format can be obtained by running /version, or using the F3 + V debug hotkey.

Pack formats help Minecraft identify whether a resource or data pack was built for the correct version of the game. If the format number in a pack's pack.mcmeta file is higher than the one the game supports, the pack appears as "incompatible". This system ensures that new pack features introduced in later versions do not cause crashes or missing content in older ones.

Each pack format corresponds to specific internal changes in how Minecraft reads data or assets. These include updates to registries, loot tables, tags, advancements, and model syntax. Both resource packs and data packs use the same numbering system but apply it differently: