Minecraft UUID Lookup
Get any Java Edition player's UUID and skin from their username, or the offline-mode UUID a cracked server would hand them.
Java Edition accounts only. Bedrock uses XUIDs, which are not Mojang UUIDs.
Try
The UUID, both formats, and the skin land here.
Bulk lookup
Paste up to 20 usernames and get every account UUID back, dashed and trimmed, with a CSV to copy.
Usernames, one per line (max 20)
| Username | UUID (dashed) | UUID (trimmed) | Status |
|---|---|---|---|
| Results land here, one row per username. | |||
Resolve a whole whitelist in one go. Lookups run one at a time, 300 ms apart, against the same profile data as the single lookup above.
whitelist.json and ops.json
Offline UUIDs for a whole list of names, formatted as the two files a cracked server reads. Nothing here touches the network.
3 names
[
{
"uuid": "b50ad385-829d-3141-a216-7e7d7539ba7f",
"name": "Notch"
},
{
"uuid": "a762f560-4fce-3236-812a-b80efff0b62b",
"name": "jeb_"
},
{
"uuid": "4d258a81-2358-3084-8166-05b9faccad80",
"name": "Dinnerbone"
}
][
{
"uuid": "b50ad385-829d-3141-a216-7e7d7539ba7f",
"name": "Notch",
"level": 4,
"bypassesPlayerLimit": false
},
{
"uuid": "a762f560-4fce-3236-812a-b80efff0b62b",
"name": "jeb_",
"level": 4,
"bypassesPlayerLimit": false
},
{
"uuid": "4d258a81-2358-3084-8166-05b9faccad80",
"name": "Dinnerbone",
"level": 4,
"bypassesPlayerLimit": false
}
]Offline mode against online mode
Which UUID a server uses is decided by one line in server.properties, and the two are not interchangeable.
| Property | Offline mode | Online mode |
|---|---|---|
| UUID version | 3 (name hash) | 4 (random, issued by Mojang) |
| Where it comes from | MD5 of the name | Mojang's account records |
| Survives a rename | No, a new name is a new player | Yes |
| Proves who you are | No | Yes |
Offline-mode UUID
Version 3, derived from the name and nothing else.
Every offline-mode server computes this same value with no help from Mojang, which is why this page can too. It is what a cracked server, its whitelist.json and its playerdata folder all key on.
Online-mode UUID
Version 4, issued by Mojang when the account was made.
It is not derived from the name, so no offline calculation can reach it. That is what the account lookup above is for: it asks the public profile data for the real one.
Nothing verifies a name in offline mode, so anyone who types a whitelisted username gets that username's UUID and walks in with its permissions and its inventory. Treat an offline whitelist as a convenience, not a lock, and put a login plugin in front of it if accounts matter. Switching online-mode later re-identifies everyone: budget an afternoon for migrating player data, and take a backup first.
How it works
Looking up an account UUID
- Type a Minecraft Java Edition username, or paste an existing UUID, into the box.
- Press Look up or hit Enter.
- Click a value to copy it. Both the dashed and the trimmed format are shown, along with the player's current skin.
About UUIDs
Every Minecraft account has a UUID, a 32-character code like 069a79f4-44e9-4726-a5be-fca90e38aaf5 that never changes, even when the player renames. Servers, plugins and mods use UUIDs instead of names for whitelists, bans, permissions and stats, because names can change and UUIDs cannot.
The account lookup resolves a current username to its UUID using Mojang's public profile data, shows the account's current skin, and gives you both formats: dashed, used in most config files and server commands, and trimmed, used by some APIs and databases.
Typical uses: adding players to a whitelist.json, checking who owns a name, setting up per-player permissions, or grabbing a skin for reference.
How Minecraft builds an offline-mode UUID
When a server runs with online-mode=false, nobody checks the joining player against Mojang, so the server cannot be told what their UUID is. It invents one from the only thing it has, the name they typed:
- Join the text OfflinePlayer: to the username exactly as typed, giving OfflinePlayer:Notch.
- Take the MD5 of those UTF-8 bytes: 16 bytes of hash.
- Overwrite the top half of byte 6 with 3 (the version nibble) and force the top two bits of byte 8 to 10 (the RFC 4122 variant).
- Print it as hex with the usual 8-4-4-4-12 dashes.
That is exactly Java's UUID.nameUUIDFromBytes, which vanilla, Spigot, Paper, Fabric and Forge all call. The result is a version 3 UUID, and you can spot one by the 3 at the start of the third group. Because the recipe is fixed, the same name gives the same offline UUID on every cracked server that has ever run. The offline mode computes it in your browser, so no name leaves the page.
Using an offline UUID in whitelist.json and ops.json
Both files sit next to server.properties in the server folder, and both match players by UUID rather than by name. On an offline-mode server the UUID they need is the offline one, not a Mojang one. Paste a Mojang UUID into an offline whitelist and the player is never recognised.
- Stop the server. Editing these files while it runs gets your changes overwritten on shutdown.
- Paste the generated block over the whole file, or merge the entries into the existing array.
- Start the server, or run /whitelist reload if it is already up.
The same UUIDs go into banned-players.json, into world/playerdata/<uuid>.dat, and into most plugin databases: LuckPerms, Essentials and CoreProtect all key on it. If a player renames on a cracked server they become a brand new person with an empty inventory, because the name is the identity.
Questions
What is a Minecraft UUID?
A UUID is a permanent unique ID assigned to every Minecraft account. Unlike usernames, it never changes, so servers use it to track players across name changes.
Does this work for Bedrock Edition?
No. Bedrock uses XUIDs (Xbox Live IDs), not Mojang UUIDs. This tool covers Java Edition accounts only.
Can I look up name history?
Mojang removed the public name-history API in 2022, so no site can show verified name history anymore. Current name and UUID are always available.
Why do I need the trimmed UUID?
Some databases and APIs store UUIDs without dashes. They are the same value, so this page gives you both and you paste whichever format the software expects.
How does Minecraft generate an offline UUID?
It takes the text OfflinePlayer: followed by the exact username, hashes those bytes with MD5, then overwrites the version nibble with 3 and sets the two RFC 4122 variant bits. That is what Java's UUID.nameUUIDFromBytes does, so the answer is a version 3 UUID and it is identical on every offline-mode server in the world.
Is an offline UUID case-sensitive?
Yes. Notch and notch are different strings, so they hash to completely different UUIDs. Type the username exactly as the player types it at the login screen, capitals and underscores included, or the whitelist entry will not match them.
What happens to player data when I switch online-mode?
Everyone gets a different UUID, so inventories, advancements, ender chests, permissions, homes and balances all look wiped. Nothing is actually deleted. The old playerdata files are still in the world folder under the old UUID, they are just no longer matched to anybody.
Can two people end up with the same offline UUID?
Anyone who types a given username gets that username's UUID, because nothing is verified against Mojang. An offline whitelist therefore keeps out only people who have not guessed a listed name. It is a speed bump, not authentication. Use a login plugin if accounts matter.
Does this page look anything up online?
The offline mode does not. Its MD5 runs in your browser, no name ever leaves the page, and it keeps working with the network off. The account lookup does make a request, because a genuine Mojang account UUID cannot be derived from a name at all.