How Much RAM Does a Minecraft Server Need?
Quick answer
Most Minecraft servers need less RAM than people expect: 4 GB runs a vanilla server or a Paper server with a few plugins for up to about ten players, 6 to 8 GB suits 10 to 30 players with plugins, and 10 to 16 GB covers large communities and heavy modpacks. Past that point extra memory rarely helps, because lag almost always comes from the single main thread, view distance, farms and freshly generated terrain, not from a lack of RAM.
How much RAM does a Minecraft server need by player count?
The right amount of RAM for a Minecraft server comes down to three things: how many players are online at the same time, how spread out they play, and what the server runs. A vanilla or Paper server with a handful of plugins is light, and each plugin that caches data adds a little. A modpack can multiply memory use several times over, because every mod loads its own blocks, items, recipes and world-generation data before a single player joins. The table below gives realistic starting points for a Java Edition server with a view distance around 8 and a pre-generated world.
Treat these numbers as floors, not targets. Paper's own documentation, following Aikar's long-standing advice, recommends at least 6 to 10 GB no matter how few players you have, because the garbage collector runs more smoothly with headroom. That advice is about smoothness, not survival: a friends server on 4 GB runs fine, but if you notice periodic stutters from garbage collection, moving up one step is the cheapest fix. Count peak concurrent players rather than total members. A community of 200 with 25 people online in the evening is a 25-player server.
| Players online | Vanilla or Paper, few plugins | Paper with many plugins | Modpack (Fabric, NeoForge, Forge) |
|---|---|---|---|
| 1 to 5 | 2 to 4 GB | 4 GB | 6 to 8 GB |
| 5 to 10 | 4 GB | 4 to 6 GB | 8 to 10 GB |
| 10 to 25 | 4 to 6 GB | 6 to 8 GB | 10 to 12 GB |
| 25 to 50 | 6 to 8 GB | 8 to 12 GB | 12 to 16 GB |
| 50 to 100 | 8 to 12 GB | 12 to 16 GB | 16 GB or more, plus a fast CPU |
| 100+ | Split across several servers behind a proxy | Split across several servers behind a proxy | Rarely practical on one server |
Why doesn't more RAM always make a server faster?
Extra RAM only helps when the server is actually short of memory; once loaded chunks, entities and plugin data fit comfortably, the rest sits idle. Minecraft runs its world simulation on one main thread, which has 50 milliseconds to finish each tick if it wants to hold 20 ticks per second. When that thread runs out of time because of too many mobs, hoppers or redstone, the fix is less work per tick or a faster CPU core. Doubling the memory changes nothing, which is why a laggy 16 GB server is such a common sight.
Oversizing can also backfire. Java needs memory beyond the heap you set with Xmx for its own code, threads and network buffers, so Aikar's guidance is to keep Xmx roughly 1000 to 1500 MB below what the machine or container can provide. Skip that margin and the operating system starts swapping to disk or kills the process outright. A very large heap also hides memory leaks: a badly written plugin can leak for days before anyone notices, and if the collector ever falls back to a full collection, that pause grows with the size of the heap.
The flip side matters just as much: too little RAM is worse than too much. When the heap is nearly full, the garbage collector runs again and again, each pass frees less, and players feel it as rhythmic stutters until the server eventually crashes with an OutOfMemoryError. The goal is enough headroom to keep collections short and infrequent, and nothing beyond what your measurements show you actually use.
What are Aikar's flags and should you use them?
Aikar's flags are a set of Java startup options, published in the Paper documentation, that tune the G1 garbage collector for the way Minecraft uses memory. The server creates enormous numbers of short-lived objects, which the Paper docs put at 800 MB per second or more on a 30-player server. With default settings, some of those objects get promoted into the old generation and are only cleaned up later in heavier collections. The flags enlarge the young generation so most garbage dies young and is swept up in quick, cheap passes.
The key ideas are easy to follow even if the full list looks intimidating. Xms and Xmx are set to the same value so the heap never resizes, and AlwaysPreTouch claims all of it at startup. A pause goal of 200 milliseconds, at most four ticks, tells G1 to keep individual pauses short. DisableExplicitGC stops plugins from forcing needless full collections, and a few G1 region and threshold settings trim collection overhead. For heaps above 12 GB, Aikar's original write-up adjusts a handful of those values.
Use them on Paper, Purpur, Fabric, NeoForge and Forge alike, since they are JVM options rather than plugin settings. Copy the current list from Paper's documentation instead of an old forum post, and keep the memory value matched to your plan. Remember what they do: they smooth out garbage collection stutter, but they don't make an overloaded main thread any faster. Some admins with large heaps and spare cores try ZGC, which keeps pauses extremely short at the cost of extra CPU and memory, but G1 with Aikar's flags remains the documented default.
How do view distance and simulation distance affect RAM?
View distance is the biggest RAM lever you control. The server keeps a square of chunks loaded around every player, so the default view-distance of 10 means roughly 21 by 21, or about 441 chunks per player, while 8 drops that to about 289 and 6 to about 169. Players building together share the same chunks, but players spread across the map each hold a square of their own. That is why ten explorers use far more memory than ten people living in one town.
Simulation distance decides how far from each player mobs move, crops grow and redstone runs. It is mainly a CPU setting, but it also controls how many entities are active in memory at once. Busy servers commonly settle on a view distance of 7 or 8 and a simulation distance of 4 to 6: players still see a good distance, while the heavy ticking only happens close to them. Spigot and Paper also let you set both values per world in spigot.yml, so a resource world can run lower values than the main world.
Why should you pre-generate your world with Chunky?
Pre-generating builds the terrain before players arrive, so the server doesn't have to create new chunks during play. Generating a chunk means shaping terrain, placing caves and structures, and calculating lighting, which makes it one of the heaviest jobs a server does. A single player flying with elytra or racing a boat across ice can demand dozens of fresh chunks every second, pushing CPU and memory usage up for everyone else online.
Chunky is the standard tool for the job and runs on Paper, Spigot, Folia, Fabric, NeoForge, Forge and Sponge. Set a center and radius, for example chunky radius 5000 followed by chunky start, and let it run while the server is quiet; a large radius can take hours, and you can pause and resume it. When it finishes, set a vanilla world border just inside the generated area with worldborder set, which takes a diameter, so 10000 for a 5000-block radius. A pre-generated world takes more disk space, so check your storage before you start.
How much RAM do modpacks need?
Modpacks need more RAM because every mod loads its content into memory at startup, before anyone joins, and tech and automation mods keep adding machines, pipes and stored items as the world grows. Mod count is the quickest guide, but content matters too: fifty world-generation and dimension mods weigh more than a hundred small quality-of-life tweaks. Most packs state a recommended server memory on their download page or in their server files, so start there and adjust once you have watched real usage.
Every player needs the pack installed as well, so their own PCs need spare memory too. Start with the smallest amount the pack recommends, add players gradually, and upgrade when the heap stays high even after garbage collection. On TheCrewHost, NeoForge servers start at 6 GB of RAM, Minecraft plans range from 4 GB to 32 GB, and you can move to a larger plan whenever you need to.
| Pack type | Typical size | Starting RAM | What to watch |
|---|---|---|---|
| Performance or vanilla-plus pack (Fabric) | Up to about 50 mods | 4 to 6 GB | Behaves close to vanilla |
| Themed or adventure pack | About 100 to 200 mods | 6 to 10 GB | New dimensions and structures raise memory use |
| Kitchen-sink pack | 250 to 400+ mods | 10 to 16 GB | Long startup; memory keeps growing with the world |
| Heavy tech or automation pack | Varies | 10 to 16 GB or more | Big factories stress the CPU as much as RAM |
When does CPU single-thread speed matter more than RAM?
CPU speed matters more than RAM as soon as memory is sufficient, which on a well-sized server is nearly always. The main thread handles entities, block updates, redstone, crop growth and every plugin event one after another, and it has 50 milliseconds per tick to get through all of it. Paper moves chunk loading, chunk generation and some networking onto other threads, so extra cores help at the edges, but the speed of a single core still decides how much world you can simulate before ticks start running late.
The telltale sign is lag while memory looks fine: MSPT climbs above 50, TPS drops below 20, yet heap usage after garbage collection sits well below the maximum. That server needs less work per tick or a faster core, not more RAM. Folia is the one design that spreads ticking across cores, and it only pays off on very large, spread-out servers whose plugins support it. TheCrewHost's game servers run on AMD Ryzen 9 9950X processors, a current desktop-class chip with high per-core clock speeds, together with DDR5 memory and NVMe SSDs.
How can you tell if your server is running out of RAM?
Don't judge by the memory graph in a control panel alone. With Xms equal to Xmx and AlwaysPreTouch enabled, Java claims its entire heap at startup, so the process looks full from the first minute even when it isn't. What matters is how much of the heap is still in use right after a garbage collection. A healthy server draws a sawtooth pattern, climbing between collections and dropping back to a similar baseline each time.
The spark profiler, bundled with Paper since 1.21 and available as a mod for Fabric, NeoForge and Forge, shows this directly. spark health --memory reports detailed JVM memory usage, spark gc shows how often collections run and how long they take, and spark heapsummary lists which object types fill the heap, which is how you catch a leaking plugin. The real warning signs are a baseline that keeps rising hour after hour, collections firing every few seconds, or an OutOfMemoryError in the logs.
Size your server's RAM in 7 steps
- 1
Estimate peak players
Count how many players are online at your busiest hour, not total members, and decide whether you are running vanilla, plugins or a modpack.
- 2
Pick a starting amount
Use the table in this guide or the modpack's own recommendation, and start one step higher if you expect to grow within a few weeks.
- 3
Set the Java memory flags
Set Xms and Xmx to the same value with Aikar's flags, leaving roughly 1000 to 1500 MB below the machine or container limit for Java's own overhead.
- 4
Pre-generate and add a border
Run Chunky over the area players will use, then set a world border so exploration no longer triggers live chunk generation.
- 5
Tune view and simulation distance
If the server gets busy, set view-distance to 7 or 8 and simulation-distance to 4 to 6, then restart so the change takes effect.
- 6
Measure at peak time
Check spark health --memory and spark gc during your busiest hour, and watch the heap baseline after collections over several days.
- 7
Upgrade only on evidence
Add RAM when the baseline stays high or you hit an OutOfMemoryError; if MSPT is high while memory is to spare, optimize instead of upgrading.
Frequently Asked Questions
Is 4 GB of RAM enough for a Minecraft server?
For most small groups, yes. 4 GB comfortably runs a vanilla or Paper server for up to about ten players with a normal set of plugins, as long as the world is pre-generated and view distance is sensible. It is too little for most modpacks and tight for 20 or more players on a plugin-heavy server. If you notice garbage collection stutters, 6 GB gives the collector the headroom Paper's documentation recommends.
How much RAM does a Minecraft server use per player?
There is no fixed per-player figure, because the cost depends on where players are. Players building in the same base share loaded chunks and add very little, while each player exploring alone keeps a few hundred chunks of their own loaded at the default view distance. The entities they create, such as farms and dropped items, add more on top. Peak concurrent players and view distance are better guides than any per-player number.
Does more RAM increase TPS?
Only if the server was genuinely short of memory. A starved heap causes constant garbage collection and stutters, and fixing that does raise TPS. Once memory is sufficient, TPS depends on how much work the main thread does each tick, so more RAM changes nothing. Check with spark: if MSPT is high while the heap after collection sits well below its limit, the bottleneck is CPU time, not memory.
Should I give Minecraft all the RAM on my machine?
No. Java uses memory beyond the Xmx heap for its own code, threads and network buffers, and the operating system needs room as well. Aikar's guidance is to set Xmx about 1000 to 1500 MB below what is available; otherwise the server can start swapping to disk or get killed by the system's out-of-memory handler. On a hosted plan, stick to the panel's memory setting instead of forcing a bigger heap with custom flags.
How much RAM does a Bedrock server need?
Bedrock Dedicated Server is a native program rather than a Java application, so there is no garbage collector to feed, and it generally uses less memory than a Java server for the same group. 2 to 4 GB suits a small group of friends, while more players, large add-ons or a higher tick-distance push that up. If Bedrock players join a Java server through Geyser, size it as a Java server, since the Java server does the real work.
How much RAM does a Velocity proxy need?
Far less than the game servers behind it, because a proxy only forwards connections between players and backend servers. Velocity's documentation suggests roughly 512 MB of heap per 500 players, plus about 1 GB of extra room, so small and mid-sized networks run comfortably on a modest allocation. Spend the bulk of your memory budget on the backend servers, where the world simulation actually happens.
Can I add more RAM later if my server grows?
Yes, and starting small then upgrading is usually smarter than guessing high. Memory needs grow with peak players, world size and mods, so measure for a week or two before deciding. At TheCrewHost you can move to a higher plan at any time, from Bronze with 4 GB through Silver, Gold, Platinum, Diamond and Emerald up to Xtreme with 32 GB. Take a backup before any major change to your server.
