Minecraft Server Calculator

How much RAM a Minecraft server really needs

A Minecraft server's memory does not depend only on how many players join, but on how much world is loaded at once. Every player drags an area of chunks around with them, set by the view distance, and those chunks have to be held in memory and simulated every tick.

The server type changes the maths as much as the players do. Paper and Purpur optimise heavily compared to Vanilla; Forge and Fabric with large modpacks can triple usage because of the blocks, entities and recipes they add. That is why the calculator asks for the type first and the plugins second.

How to use the calculator

1. 1Pick the server type (Paper, Vanilla, Forge, Fabric…) and how many players you expect at the same time at peak, not per month.
2. 2Adjust the view distance: dropping it from 10 to 8 chunks is the fastest way to win back TPS and memory with barely any visible difference in game.
3. 3Tick the extras you will actually run. A pregenerated world and a Dynmap change the result far more than people expect.

Frequently asked questions

How much RAM for 20 players?

With Paper and a few plugins, 4 GB is plenty. With a mid-sized Forge or Fabric modpack count on 8 GB as a floor, and 12 GB if the modpack is one of the big ones.

Is more RAM always better?

No. Past a point, assigning more memory only makes Java's garbage collector pauses longer. Before jumping to 16 GB for no reason, tune the view distance, pregenerate the world and check which plugins you can drop.

Paper or Vanilla?

Paper, unless you need behaviour identical to the original. Paper keeps gameplay intact while optimising entity movement and chunk loading, which is exactly where TPS goes.

Does view distance matter much?

Enormously: it is the single variable that moves the most memory and CPU. Every extra chunk is multiplied per connected player, so going from 12 to 8 chunks can cut almost half the server's work.