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Random Minecraft UUID Generator

Generate Minecraft UUIDs for online and offline mode - Version 4 random UUIDs and Version 3 username-based UUIDs

[ Minecraft UUID Generator - Quick Summary ]

What: Minecraft player UUIDs for online mode (v4 random) or offline mode (v3 username-based MD5 hash). Format: 8-4-4-4-12 hexadecimal pattern.

When to use: Minecraft server development, plugin testing, player data migration, whitelist management, offline server configuration, development environments.

Example: f81d4fae-7dec-11d0-a765-00a0c91e6bf6

Security/Important: For testing only. Online mode (v4) requires Mojang authentication. Offline mode (v3) allows player impersonation. Username case-sensitive in offline mode.

Our Minecraft UUID generator creates player UUIDs for both online (authenticated) and offline (cracked) Minecraft servers. Generate Minecraft UUIDs using Version 4 (random) for online mode with Mojang authentication, or Version 3 (name-based MD5) for offline mode using username hashing. Perfect for server development, plugin testing, player data migration, and whitelist management. Our free UUID generation API supports both Minecraft UUID formats with cryptographically secure randomness for online mode and deterministic hashing for offline mode. Export your generated Minecraft player UUIDs as text, CSV, or JSON for easy integration into server configurations.

What is a Minecraft UUID?

Minecraft uses UUIDs (Universally Unique Identifiers) to uniquely identify players, entities, and game objects. The type of UUID used depends on whether the server is running in online (authenticated) or offline (cracked) mode.

Online Mode (v4 Random): Official Minecraft servers with Mojang authentication use Version 4 UUIDs, which are randomly generated when you register a Minecraft account. These UUIDs are permanent and tied to your account, ensuring global uniqueness and preventing player impersonation.

Offline Mode (v3 Username-based): Offline servers generate Version 3 UUIDs based on an MD5 hash of "OfflinePlayer:" followed by the username. These are deterministic - the same username always produces the same UUID. Note that usernames are case-sensitive, so "Steve" and "steve" generate different UUIDs.

Online vs Offline Mode Explained

Online Mode (Authenticated)

  • Requires legitimate Minecraft account purchased from Mojang
  • Server validates player identity with Mojang authentication servers
  • Uses Version 4 (random) UUIDs assigned when account was created
  • UUIDs are permanent and globally unique
  • Recommended for public servers to prevent impersonation

Offline Mode (Cracked)

  • No Mojang authentication required
  • Server generates UUID based on username using MD5 hash
  • Uses Version 3 (name-based) UUIDs with "OfflinePlayer:" namespace
  • Same username always produces same UUID (deterministic)
  • Players can impersonate others if they know the username
  • Commonly used for private servers and development/testing

Common Use Cases

→ Server Development: Generate test UUIDs for offline mode plugin development
→ Player Data Migration: Convert between online and offline UUIDs when changing server modes
→ Database Management: Generate UUIDs for player data storage and retrieval
→ Plugin Testing: Create multiple offline UUIDs for testing multi-player scenarios
→ Whitelist Management: Generate UUIDs for adding players to server whitelists

Configuration Options

Minecraft Mode (Online/Offline)

Choose between Online Mode (Version 4 random UUIDs for authenticated servers) or Offline Mode (Version 3 name-based UUIDs for cracked servers). Online mode UUIDs are randomly generated and require Mojang authentication. Offline mode UUIDs are deterministic and generated from the player's username.

Username (Offline Mode Only)

For offline mode, enter the exact in-game username (case-sensitive). The UUID is generated using MD5 hash of "OfflinePlayer:{username}". The same username will always produce the same UUID, making it deterministic and reproducible. Username must match the player's in-game name exactly, including capitalization.

Count (1-100)

Number of UUIDs to generate. For online mode, generates multiple random v4 UUIDs. For offline mode with a single username, generates the same UUID multiple times (useful for verification). Use count of 1 for offline mode unless testing.

How to Generate Minecraft UUIDs

[STEP 1] Select Minecraft Mode

Choose between Online Mode (v4 random UUIDs for authenticated Mojang servers) or Offline Mode (v3 username-based UUIDs for cracked servers). Online mode is recommended for public servers to prevent player impersonation.

[STEP 1] Configure Parameters

For offline mode, enter the player's exact username (case-sensitive). For online mode, simply set the count. The username in offline mode must match the in-game name exactly, including capitalization, as "Steve" and "steve" produce different UUIDs.

[STEP 1] Generate and Export

Click Generate to create your Minecraft UUIDs. Copy individual UUIDs or export all results as text, CSV, or JSON format. The mode (online/offline) and version information are included in the metadata for reference.

Minecraft UUID Best Practices

  • _ Online Mode for Public Servers: Always use online mode for public servers to prevent player impersonation. Online mode validates player identity with Mojang authentication servers, ensuring secure player identification.
  • _ Case Sensitivity in Offline Mode: Offline UUIDs are case-sensitive because they use MD5 hashing. "Steve" and "steve" produce completely different UUIDs. Always use the exact capitalization of the player's in-game name.
  • _ Data Migration Planning: When switching between online and offline modes, all player UUIDs change. Plan for UUID conversion using plugins like UUIDConverter, and always backup your server data before attempting migration.
  • _ Plugin Compatibility: Verify that your server plugins support the UUID format your server uses. Some plugins may have different behavior for online vs offline UUIDs, particularly when handling player data persistence.
  • _ Backup Before Mode Changes: Always backup player data, world files, and plugin configurations before changing server authentication modes. UUID changes affect player inventories, permissions, and all stored player data.
  • _ Testing with Offline Mode: Use offline mode UUIDs for local development and testing environments. This allows you to test multi-player scenarios without requiring multiple Mojang accounts or authentication servers.

Technical Implementation

Minecraft uses two different UUID generation methods depending on server authentication mode. Online mode uses cryptographically secure random generation (CSPRNG) for Version 4 UUIDs, while offline mode uses MD5 hashing for Version 3 UUIDs with a specific namespace.

// Online Mode (Version 4 - Random UUID)
Algorithm: CSPRNG Random Generation
1. Generate 128 random bits using CSPRNG
2. Set version bits (bits 48-51) to 0100 (version 4)
3. Set variant bits (bits 64-65) to 10 (RFC 4122)
4. Format as 8-4-4-4-12 hexadecimal pattern
Result: xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx

// Offline Mode (Version 3 - Name-based UUID)
Algorithm: MD5 Hash-based Generation
1. Create input string: "OfflinePlayer:{username}"
2. Compute MD5 hash (128-bit output)
3. Set version bits (bits 48-51) to 0011 (version 3)
4. Set variant bits (bits 64-65) to 10 (RFC 4122)
5. Format as 8-4-4-4-12 hexadecimal pattern
Result: Deterministic UUID for username

// Format Specification
Pattern: 8-4-4-4-12 (hexadecimal digits)
Example: f81d4fae-7dec-11d0-a765-00a0c91e6bf6
         ^^^^^^^^ ^^^^ ^^^^ ^^^^ ^^^^^^^^^^^^
         time_low mid  hi   clk  node/hash

// UUID Version Detection
Version 3 (MD5):    xxxxxxxx-xxxx-3xxx-xxxx-xxxxxxxxxxxx
Version 4 (Random): xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx
                          Position 14 ^^^^

API Access for Developers

GET https://generate-random.org/api/v1/generate/uuids
VIEW FULL API DOCUMENTATION →

Frequently Asked Questions

What's the difference between online and offline Minecraft UUIDs? ▶
Online mode UUIDs are Version 4 (random) generated by Mojang when you create a Minecraft account. They're permanent and tied to your account. Offline mode UUIDs are Version 3 (name-based) generated from your username using MD5 hash. The same username always produces the same offline UUID, making them deterministic but allowing player impersonation.
Can I use the same UUID for both online and offline mode? ▶
No. Online and offline UUIDs are completely different. When a server switches between modes, all player UUIDs change, which can cause issues with player data, permissions, and inventories. Always backup your data before switching modes. You may need to use a plugin like UUIDConverter to migrate player data.
Why are offline UUIDs case-sensitive? ▶
Offline UUIDs are generated using MD5 hash of "OfflinePlayer:" followed by the exact username. Since MD5 hashing is case-sensitive, "Steve" and "steve" will produce completely different UUIDs. Always use the exact capitalization of the player's in-game name when generating offline UUIDs.
How do I convert player data between online and offline UUIDs? ▶
Converting requires a plugin or manual database migration. You'll need to rename player data files and update database entries with the new UUIDs. Popular plugins like UUIDConverter can automate this process. Always backup your server before attempting conversion, as the process is complex and errors can result in data loss.
Can players on offline mode servers impersonate each other? ▶
Yes. Since offline mode doesn't validate accounts with Mojang, anyone can join with any username and receive that username's UUID. This is why online mode is recommended for public servers. Use offline mode only for private servers, development, or testing where player impersonation isn't a concern.
Do Minecraft Bedrock and Java Edition use the same UUIDs? ▶
No. Bedrock Edition uses a different UUID system tied to Xbox Live/Microsoft accounts. This tool is specifically for Java Edition UUIDs. Bedrock UUIDs follow a different format and cannot be used interchangeably with Java Edition. Each platform maintains its own player identification system.

[ HOW TO CITE THIS PAGE ]

APA Style:
Generate-Random.org. (2025). Random Minecraft UUID Generator. Retrieved from https://generate-random.org/minecraft-uuid
Web Citation:
Random Minecraft UUID Generator - Generate-Random.org (https://generate-random.org/minecraft-uuid)