Updated 2026-10-16 · All guides
How much RAM does a Minecraft server need?
Giving your server the right amount of memory (RAM) is one of the easiest ways to avoid lag. Too little and it stutters or crashes. Too much and you take memory away from Windows, and from Minecraft itself if you play on the same PC.
Starting points
These are rules of thumb for a typical survival world. Large builds, lots of loaded farms or a big view distance push them up.
| Server | Players | RAM to give it |
|---|---|---|
| Vanilla or Paper | 1–5 | 2–3 GB |
| Vanilla or Paper | 5–15 | 4 GB |
| Paper | 15–30 | 6 GB |
| Fabric, a few mods | 1–10 | 4–5 GB |
| Fabric, big modpack | 1–10 | 6–8 GB+ (check the pack's own advice) |
Leave memory for everything else
Your PC also needs RAM for Windows, your browser, Discord and, if you play on the same machine, the Minecraft client, which uses roughly 2–4 GB on its own. A common setup:
- 8 GB PC, playing on it too: give the server 2–3 GB.
- 16 GB PC: 4–6 GB for the server is comfortable.
- 32 GB PC: plenty of room. Even 8 GB for a modpack leaves lots spare.
If the whole computer starts to feel slow while the server runs, it's probably using too much of your memory.
Why more isn't always better
Java reclaims unused memory in "garbage collection" passes. With far more memory than it needs, the server can build up more to clean at once, and on some setups that shows up as a short freeze. Past the point where it stops running out, extra RAM rarely makes a server faster. Tuned settings help much more. HostCraft uses the startup flags recommended by the Paper team (often called "Aikar's flags"), which keep these pauses short.
Signs your server needs more RAM
- The console shows
OutOfMemoryError, or the server crashes when lots of chunks load. - Memory use sits at the maximum all the time, which HostCraft's Performance tab graphs.
- Lag spikes get worse the longer the server has been running.
Lag isn't always about memory. A slow CPU, a huge view distance, or one giant mob farm are common causes too. Try lowering the view distance to 8–10 and the simulation distance to 6–8 before throwing more RAM at the problem.
Other things that make a bigger difference
- Use Paper or Purpur instead of Vanilla, or performance mods on Fabric.
- Pre-generate your world with a plugin like Chunky, so new chunks aren't generated while people explore.
- Run it on an SSD, not an old hard drive.
- Keep entity counts sensible. Thousands of items or animals in one place will lag any server.