How to disable online mode on a Minecraft server

Minecraft Java Edition and Bedrock Edition servers run with online mode enabled by default. In this mode, the server contacts the official Minecraft session servers to authenticate players. Keeping online mode enabled is strongly recommended, as disabling it introduces security and impersonation risks.

When You Should Disable Online Mode

Disabling online mode is often referred to as running a cracked Minecraft server. While we do not support piracy, there are legitimate scenarios where offline mode is useful or necessary.

Some valid reasons to disable online mode include:

Minecraft session servers are temporarily offline
Playing on a LAN without internet access
Using a proxy setup (Velocity or BungeeCord) where authentication happens at the proxy
Living in a region where purchasing or accessing Minecraft is not officially possible

How to Disable Online Mode in Minecraft

To switch your server to offline mode:

Open your server’s server.properties file.
Locate the line: online-mode=
Change the value from true to false.

Your configuration should look like this:

online-mode=false

Restart your server to apply the change.

Risks of Running a Minecraft Server in Offline Mode

Disabling online mode removes the built‑in authentication system provided by Mojang. This means:

Anyone can join using any username, including names of existing players or operator accounts
Players can impersonate staff or gain unauthorized privileges
Most cracked servers rely on third‑party authentication plugins to require in‑game registration and prevent impersonation

Encryption Limitations on Older Versions

Before Minecraft Java Edition 1.20.5, offline mode servers could not use encrypted connections. As a result:

Player traffic was vulnerable to eavesdropping
Man‑in‑the‑middle attacks were easier on unsecured networks

Modern versions support encrypted connections even in offline mode, but the impersonation risks remain unchanged.