Free tool
Minecraft server RAM calculator
How much memory your server actually needs — without the guesswork.
Recommended
4 GB RAM
Paper / Spigot with plugins, ~10 players
Comfortable headroom
6 GB RAM
For big builds, exploration bursts and chunk pregen
Plans resize without reinstalling — start at the recommendation and scale if TPS says so.
See 4 GB plansThe estimate uses a base heap per server flavor plus a per-player factor, rounded up to common plan sizes. It deliberately leans conservative: the most common mistake in server hosting is putting a 250-mod pack on a 2 GB plan and blaming the pack.
Two things the calculator can't see: view distance (each +2 roughly doubles loaded chunks per player) and world age (entity-heavy farms grow memory over time). If your TPS drops while memory sits near the ceiling, move up a tier; if memory idles half-empty, you can safely size down.
Common questions
How much RAM does a vanilla Minecraft server need?
2 GB runs a small vanilla server for a handful of friends comfortably. Beyond roughly 10 concurrent players, or with a large view distance, step up to 4 GB.
How much RAM do modpacks need?
Light packs (up to ~100 mods) want 5-6 GB, mid-size packs 6-8 GB, and kitchen-sink packs like All the Mods 10 or RAD genuinely need 10 GB or more. Modded servers also load hundreds of extra classes and registries at boot, which is why a pack that runs on your PC with 6 GB can still crash a 4 GB server.
Is more RAM always better?
No. Oversized heaps make Java's garbage collector do rarer but longer sweeps, which shows up as lag spikes. Size the heap to the workload and spend the savings on better CPU — Minecraft's main loop is single-thread bound, so per-core speed usually matters more than RAM past the requirement.
Does player count or mod count matter more?
Mods set the floor, players set the growth. A heavy pack needs 10 GB before anyone joins; each additional player then adds roughly 100-150 MB on modded servers (about 50 MB on vanilla) for their loaded chunks and entities.
RAM sorted — now pick a plan
Dedicated (never oversold) memory, burst CPU, and resizes without reinstalling.