nurshia

UUID Converter

Convert Minecraft UUIDs between dashed, trimmed, NBT int array and most/least significant bits. Generate offline-mode UUIDs and detect Bedrock/Floodgate UUIDs.

Input

Paste a username, a UUID (with or without dashes), an NBT int array or UUIDMost/UUIDLeast. Put one per line to convert many at once — handy when moving a server between online and offline mode.

UUID

Online account
Dashed069a79f4-44e9-4726-a5be-fca90e38aaf5
Trimmed069a79f444e94726a5befca90e38aaf5
Int array[I;110787060,1156138790,-1514210135,238594805]
Most bits475826800676128550
Least bits-6503483008858150155

Version 4: a real Minecraft account, issued by Mojang. Int arrays are used in NBT since 1.16; most/least bits before that.

Look up this player

Good to know

Online vs offline UUIDs

Online-mode servers use the account UUID from Mojang (version 4). Offline-mode servers compute one from the name: MD5 of OfflinePlayer:<name> (version 3). Switching modes therefore gives every player new data.

Which format does NBT want?

Since 1.16, entity and item NBT stores UUIDs as an int array, e.g. UUID:[I;1,2,3,4]. Before 1.16 it used two longs, UUIDMost and UUIDLeast.

Bedrock players via Geyser

Floodgate gives Bedrock players a UUID whose first half is zero and whose second half is their Xbox user ID (XUID). The converter detects and decodes these.

Questions

How do I convert a whole server from offline to online mode?

Paste all player names (one per line) to get their offline UUIDs, then look up their online UUIDs and rename the files in world/playerdata, stats and advancements. Plugins keep their own data and usually have migration commands.

Is the offline UUID the same on every server?

Yes. It only depends on the exact name (case-sensitive), so “Steve” and “steve” get different offline UUIDs.

Where do I find a player’s real UUID?

Use the Player Lookup tool: it asks Mojang for the account UUID by name.