A Java Edition server needs at least 1 GB of RAM allocated. The Minecraft Wiki lists 1 GB for 1 to 4 players, 2 GB for 5 to 10 and 4 GB beyond that, on a fresh world with default settings. Plugins, mods and world size push the number up, and PaperMC suggests 6 to 10 GB for its flag set.
How much RAM a Java server needs by player count
These figures come from the Minecraft Wiki's Server/Requirements page, which covers the current Java Edition version, 26.3, and which we read on 12 October 2026. We read documentation. We did not run, load or benchmark any server.
| Tier | Players | RAM | Storage |
|---|---|---|---|
| Minimum | 1 to 4 | 1 GB | At least 150 MB for world saves |
| Middle tier | 5 to 10 | 2 GB | At least 200 MB for world saves |
| Largest tier | 10 and more | 4 GB | At least 200 MB on an SSD |
The wiki states that these assume default settings, a draw distance no higher than 10 and a new world. A major world with several camps, redstone machinery and grinders can easily more than double the requirements. Its setup tutorial says a survival server with 4 to 8 players runs on most modern hardware, that small servers want at least 2 GB, and that larger ones may need 4 GB.
The wiki also notes that a player object takes about 50 to 100 MB, but that the server often allocates much more per player. Player count alone is a weak predictor. World size and active farms matter as much.
How mods and plugins change the number
The wiki says requirements change with server software such as Bukkit and with mods, and it gives no figures for either. PaperMC's flag guide suggests at least 6 to 10 GB "no matter how few players", and says that if you cannot afford 10 GB you should give as much as you can while leaving the operating system some. That is a tuning target for Paper with its own flags, not a floor. For a modded server, size from the modpack's own page, and read our guide to hosting a modded server. Paper against Spigot covers the software choice.
ServerCore's page says it aims to optimize the server, and that features which change vanilla behaviour are off by default.
ServerCore
Java Mod by Wesley1808
Very Many Players targets high player counts on Fabric. Its own page warns that it is in early development and things are expected to break.
Very Many Players (Fabric)
Java Mod by ishland
Memory Leak Fix patches known leaks, but its page says the leaks it fixed were fixed in the game itself from 1.20.5, which makes the mod obsolete on newer releases.
Memory Leak Fix
Java Mod by FxMorin
Why Xmx is not total memory use
Xmx sets the ceiling of the Java heap. The wiki's minimum example is `-Xmn 128M -Xmx 1G`. PaperMC's docs say a server should be expected to use the entire Xmx, and that the operating system needs extra memory on top for everything that is not the game. The wiki adds that on Windows or a desktop-based Linux distribution you should have at least 1 GB of additional physical RAM so the desktop does not lag.
The wiki also describes a soft maximum, for example `-Xmn 128M -XX:SoftMaxHeapSize=1G -Xmx 2G`. The JDK tries to stay below the soft limit but may go up to Xmx when needed. PaperMC's flags set Xms equal to Xmx, because it holds that memory the heap does not use is wasted.
Why more RAM is not always better
PaperMC states that above a certain point more memory brings diminishing returns, and that buying 32 GB for a server wastes money for minimal gain. It also says the game allocates memory at a high rate, at least 800 MB per second on a 30 player server, mostly short-lived objects. How the garbage collector copes with that is a tuning question, not only a capacity one.
CPU is the other limit. The wiki says the server mostly uses one core, typically three at most, so single-core speed matters. Lots of redstone or mobs strain the CPU first. If lag comes from loaded terrain and entities, simulation distance against render distance is a cheaper fix than a bigger plan.
What to check before you buy or allocate more
- Player count, world age and active farms, using the table above as a floor for a vanilla server.
- The server software, since Paper, Fabric and NeoForge servers all differ from vanilla and the wiki gives no figures for them.
- The Java release. The wiki's tutorial says Minecraft 26.1 and later needs Java 25, and our Java update guide covers the change.
- Whether the host's RAM and CPU are guaranteed or shared, and how fast a single core is. The wiki lists both as points to compare.
- Headroom for the operating system on top of Xmx.
Where to go next
Our RAM allocation guide is about the player's own game, not a host. If you are new to hosting, what a Minecraft server is sets out the kinds you can join or run.
