About OfflineAuth
From ModrinthA lightweight authentication mod for Minecraft servers. Supports registration, login, inventory protection, brute-force prevention, and auto-login based on IP.
OfflineAuth
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A lightweight authentication mod for Minecraft servers. Supports registration, login, inventory protection, brute-force prevention, and auto-login based on IP.
> Requires TrueUUID mod as a dependency!
Features
- Register/Login/Change Password — Secure commands for players.
- Inventory Protection — Unauthenticated player's inventory is backed up and restored on login.
- Brute-force Protection — Too many failed attempts will lock the account for a configurable period and kick the player.
- IP Auto-login — Players can be automatically logged in within a set time window if they join from the same IP.
- Configurable Messages — All prompts and behaviors can be customized in
config/offlineauth/config.json. - No interference with online (premium) accounts — Only offline UUID players are affected.
- Command
/auth help— View all available commands.
Commands
/register <password> <confirm>— Register a new account./login <password>— Login to your account./changepassword <old> <new>— Change your password./auth help— Show help information.
Configuration
Edit config/offlineauth/config.json to customize:
timeoutSeconds— Kick unauthenticated players after X seconds.maxFailAttempts— Maximum login/register failures before lock/kick.failLockSeconds— Lockout duration after too many failures.autoLoginEnable— Enable/disable auto-login feature.autoLoginExpireSeconds— Time window for IP-based auto-login.messages— Customize all prompts and warnings.
Security Notice
- Auto-login (same IP) is convenient, but insecure on public computers/networks. Always warn players to protect their accounts.
- Passwords are stored in plain text (by default), use at your own risk or extend for encryption.
How to Install
- Install TrueUUID mod on your server. (Required!)
- Place the OfflineAuth mod jar in your server's
modsfolder. - Start your server once to generate the config files.
- Edit
config.jsonas needed. - Restart the server.
License
LGPLv3
Highlights
From source dataGame versions
Supports 6 Minecraft versions, the newest being 1.20.6.
Loaders
Runs on Forge.
Footprint
Rated a light load on a server.
OfflineAuth on Nxeon
From our catalogue- One-click install
- Supported on Nxeon Minecraft servers. We download it from Modrinth, place it, and restart the server.
- Server side
- Required on the server
- Server type needed
- Forge
- Server load
- light
- Smallest plan we suggest
- Minecraft — 2 GB (2 GB RAM). This follows our own load rating above, not a benchmark.
- Latest build
- 1.0.3, released 2025-10-31
Game versions by loader
| Loader | Game versions | Newest |
|---|---|---|
| Forge | 1.20.1 to 1.20.6 (6 versions) | 1.20.6 |
From 3 recorded builds of OfflineAuth.
Recent builds
| Build | Released | Game versions | Loaders |
|---|---|---|---|
| 1.0.3 | 2025-10-31 | 1.20.1 to 1.20.6 (6 versions) | Forge |
| 1.0.2 | 2025-10-06 | 1.20.1 to 1.20.6 (6 versions) | Forge |
| 1.0 | 2025-09-08 | 1.20.1 to 1.20.6 (6 versions) | Forge |
Dependencies
- Required: modrinth project fMgRLYNA (modrinth, not in our catalogue)
Declared by the newest build that lists any. Required ones are installed with it on one-click installs.
Run OfflineAuth on a Minecraft server
Pick a server or deploy a new one above; it is installed in one click.
What kind of mod it is
From the catalogQuality of life & UI
Small conveniences, tweaks and interface improvements players notice straight away.
Runs on your server
From source side supportModrinth lists OfflineAuth as required on the server. Check its Modrinth page to see whether players need it too.
Compatibility
- Game
- Minecraft
- Loaders
- Forge
- Runs on
- Serverrequired on the server
- Game versions
- 1.20.6 and 5 earlier
Verified at the source
- ✓ModrinthOfficial listing, checked 2026-10-02Open ↗
- ✓AuthorYuWan030, as published on Modrinth
- ✓LicenseLGPL-3.0-onlyFree
