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Important settings

Lag and performance

If a server lags, view-distance and simulation-distance are often important. Lower values can reduce load, but very low values make gameplay feel cramped.

Keep a copy of your current configuration

A server.properties generator is useful, but always keep a backup of the old file before replacing server settings.

Example settings and their effects

online-mode=true
enable-command-block=false
view-distance=10

These are Java server properties, not in-game chat commands. online-mode=true enables normal account authentication, enable-command-block=false disables command blocks until changed on 1.21.8 and older (1.21.9 replaced it with a game rule), and view-distance controls the server's view-distance setting. Values must be chosen for the actual server and hosting capacity, not copied blindly from a template.

Editing a live server safely

  1. Stop the server and back up the original server.properties file.
  2. Change only the settings you understand in the editor (Japanese).
  3. Keep the property names exactly as expected and avoid duplicate keys.
  4. Restart the server and review its console log for invalid values.

This editor is for Java Edition server.properties; Bedrock Dedicated Server uses a different property set. The site does not receive or change your server files automatically.

Common settings and their defaults (Java)

PropertyDefaultWhen to change it
max-players20Match what your host can handle. More slots do not cost anything until people join.
view-distance10Lower to 6–8 if the server lags with several players.
simulation-distance10Lower to 5–6 to cut CPU use; farms only run inside this range.
difficultyeasyMost survival servers use normal or hard.
gamemodesurvivalDefault mode for new players.
spawn-protection16Non-operators cannot build within this radius of spawn. Set 0 to turn it off.
white-listfalse (true from Java 26.3)Turn on for friends-only servers, then add players with /whitelist add. New 26.3 servers start with it on; set false for a public server.
enable-command-blockfalseTurn on for maps and minigames that use command blocks. Removed in Java 1.21.9; use the command_blocks_work game rule instead.
allow-flightfalsePlayers who fly for a few seconds without permission are kicked. Turn on if you use mods or plugins that let players fly.
motdA Minecraft ServerThe text shown in the multiplayer server list.
server-port25565Only change it if your host tells you to or you run several servers on one machine.

Why a change did not apply

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