How much RAM does a Minecraft server need?
Too little RAM and your server lags or crashes; too much in the wrong place and it can get worse. Here is how to choose the right amount.
Quick answer
| Players / setup | Recommended RAM |
|---|---|
| 1–5 friends, Vanilla or Paper | 2 GB |
| Up to ~15 players, a few plugins | 4 GB |
| Up to ~25 players, community server | 6 GB |
| Up to ~40 players, many plugins | 8 GB |
| Big modpacks (Forge/Fabric) or 60+ players | 12 GB or more |
These are guidelines for Paper or Vanilla. Every modpack is different — check what its authors recommend.
What uses the memory
- Loaded chunks: every player loads the area around them, so more players exploring in different places means more memory.
- View and simulation distance: a higher render distance loads many more chunks.
- Mods: modpacks with hundreds of mods can need 6–8 GB just to start.
- Plugins: most are light, but maps, big economies and minigame plugins add up.
- Entities: large farms with hundreds of animals or items cost memory and CPU.
Why giving Java all the RAM is a mistake
Java's -Xmx setting is the most memory the server may use. If you set it equal to all the RAM of the machine, the operating system has nothing left and the server gets killed or swaps to disk — which feels like terrible lag. Leave room for the system, and keep -Xms (the starting memory) lower than -Xmx so memory is used only when needed.
On EclipsiumX the split is calculated automatically for every server and network, so Java gets as much as it safely can.
Signs you need more RAM
- The console shows "OutOfMemoryError" or the server stops by itself.
- Lag spikes when many players are online, even though CPU usage looks fine.
- A modpack takes several minutes to start or fails while loading.
Before adding RAM, lower the view distance and check for a plugin or farm that is using far more than the rest — that often fixes lag for free.