How much RAM your Minecraft server needs, and how to change it

Your subscription is a pool of RAM. Each server takes a share of it while it runs; a stopped or sleeping server takes none. Every extra gigabyte in the pool is a dollar a month.

Change a server’s RAM

  1. Open Settings, General.
  2. Set Server RAM (GB) and save.
  3. Restart the server. The Java memory flags are set for you; there is no start script to edit.

If the pool is too small for the new size, the panel offers to add RAM to the plan on the spot. The Statistics tab shows the memory the server actually uses over time, which is the honest way to size it.

Numbers that work

The RAM calculator sizes a server from the player count, the modpack, plugins and Bedrock players, using what servers hosted here use. The table below is the short version.

ServerRAM
Vanilla or Paper, a few friends2 GB
Paper with 20 plugins, a community4 GB
Fabric with performance mods2 to 4 GB
A 150-mod Forge pack, a few friends6 GB
A 300-mod kitchen sink pack8 to 12 GB

Every modpack page on this site has a table for that pack, measured on our own fleet where we run it: modpacks.

More is not always better

  • Minecraft 1.12.2 and older run worse past 6 to 8 GB: the old garbage collector pauses longer with a bigger heap.
  • Lag with RAM to spare is CPU: worldgen, mob AI, redstone and big contraptions run on one thread. See Why is my server lagging?.
  • The panel warns when a server sits at its memory limit; the fix is one gigabyte at a time, not doubling.

Something missing or wrong? Tell us or ask in Discord.