How much RAM does a Minecraft server need?

How much RAM for a Minecraft server depends on what it runs. A vanilla or Paper server for a few friends needs 2 to 4 GB. A modest mod list needs 4 to 6 GB. A large modpack needs 6 GB before anyone joins and 8 GB or more with friends online. For your own player count, plugins and view distance, use the Minecraft server RAM calculator: it shows the math behind its answer.

How much RAM for a Minecraft server, by setup

These are rules of thumb, not guarantees. Figures marked with a source are that source’s own, read on 12 October 2026. “Our estimate” is what our calculator gives at the default view distance of 10.

Three things to know when you read it:

• The wiki’s figures are for a plain server. They assume default settings, a new world and a view distance no higher than 10, and they cover the server only, not the operating system.
• Paper asks for more. Paper’s documentation recommends “at least 6-10GB, no matter how few players”, and as much as you can give if that is out of reach. Our estimates are the smaller amount a server like yours should get by on.
• For a published modpack, the author’s figure wins. The FTB pages for StoneBlock 3, Direwolf20 1.20 and FTB Skies each list a minimum of 4096 MB and recommend 6144 MB. Many pack pages quote memory for a player’s own game, not for a server. If that is all you can find, treat it as the least to try.

What actually uses the memory

• The game and what you add to it. This is used before the first player joins. Our calculator starts vanilla and Paper at 1 GB, a mod loader at 2 GB and a large modpack at 6 GB.
• Chunks loaded around each player. At view-distance=10, the default, that is a square of about 441 chunks per player. At view-distance=6 it is about 169. This is why each extra player costs memory: we count 0.1 GB per player on vanilla and Paper, 0.15 GB on a mod loader and 0.5 GB on a large modpack.
• Plugins and mods. They differ a lot in size. As an average, we count 0.03 GB per plugin and 0.01 GB per mod.
• Spare room. Java frees memory in batches (garbage collection) and needs space to do it. The calculator adds 20% for this.
• Java itself. Java uses memory beyond the amount you give the game with -Xmx. Paper’s documentation says to set -Xmx about 1000 to 1500 MB below what your host gives you, and to set -Xms to the same value. Its example is 6500 MB on an 8 GB plan. Some hosts cover this overhead for you, so ask. The start script generator writes the full command.

Why more RAM does not fix lag from the processor

A Minecraft server tries to run 20 game ticks every second, which leaves 50 milliseconds for each one. How fast a tick finishes depends on the processor, not on memory. The Minecraft Wiki’s requirements ask for a CPU with “good single-core performance” and note that the server typically uses three cores at most.

So memory only has to be big enough. Paper’s documentation says “more memory does not mean better performance above a certain point”, and that buying 32 GB for one server wastes money. If ticks are slow while memory still has room, the cause is somewhere else: too many entities, a high simulation distance, a slow plugin or a busy shared processor. Our guide to reducing lag on a Minecraft server covers those.

How to see what your server really uses

Measure before you pay for more. The tool for this is spark. Paper has bundled it since version 1.21, so there is nothing to install. On Fabric, Forge and NeoForge, add the spark mod from its download page, which lists builds for Minecraft 26.3 as of October 2026.

Run these in the server console without the slash, or in game as an operator, with your usual players online:

/spark health
/spark gc
/spark heapsummary

• /spark health makes a health report with TPS, processor, memory and disk usage.
• /spark gc prints the server’s garbage collection history: how often Java had to clean up and how long it took.
• /spark heapsummary uploads a summary of what is filling the memory and gives you a link. It can point to a plugin or mod that holds far more than the rest.

Signs that you need more RAM

• The log shows OutOfMemoryError and the server crashes. This is the clearest sign. Look in logs/latest.log.
• Garbage collection never rests. /spark gc shows collections that run constantly or take a long time, and the memory figure in /spark health stays near the top afterward.

One sign points the other way. If the server is killed with no error and no shutdown messages, -Xmx is probably set too close to the plan’s limit. Lower it, as Paper advises, before you buy more memory.

Before upgrading, try the free fixes: lower view-distance in server.properties, remove plugins or mods nobody uses, and restart. The server.properties guide explains the setting.

What fits in the RAM on our free plan

A free Severoo server gets up to 6 GB of RAM. There is no player cap, so memory is the practical limit. With the full 6 GB, our calculator says these fit at view distance 10:

• A vanilla server with about 40 players.
• A Paper or Purpur server with 30 plugins and about 30 players.
• A Fabric, Forge or NeoForge server with 100 mods and up to 14 players, or 200 mods and up to 7.
• Packs with a 4096 MB minimum, such as the three FTB packs named above. Their recommended 6144 MB is the full 6 GB, so keep the group small.

Those counts are for memory alone. The processor can set a lower limit.

What does not fit well: the largest modpacks. The All the Mods guides ask for at least 6 GB allocated to the server, and FTB StoneBlock 4 lists at least 6 GB. That is everything the plan has, with nothing left for Java’s overhead or for extra players. Such a pack may start. Expect lag or crashes once friends join. A smaller pack is the honest choice on a free plan, and our page on free modded Minecraft server hosting explains what is allowed.

Not every free plan gets the full amount, so check the plans page and put your own numbers into the RAM calculator. It compares the result with the free plan for you. One condition applies whatever you run: a free server stays online 24/7 as long as you renew it. Renewing is one click, paid for with account credits that are free to collect. It is due on a schedule that depends on your plan (every few hours on some plans).