How the calculator works
Every game starts with a base: the memory the server program needs before anyone joins. Each player then adds a little, because the server keeps the area around them loaded.
Mods and plugins add more on top, and so does a big or well-explored world. The calculator adds those up for your game, then rounds up to a plan size with a safety buffer so the server never runs out at the busiest moment.
The numbers come from each game's official dedicated server requirements and from what server owners report for real groups, checked for every game we host.
Minimum, best fit or room to grow?
Bare minimum will run, but expect slowdowns when everyone is online or a lot is happening. It suits trying a game out with a couple of friends.
Best fit is what we recommend: enough memory for your group with a buffer for busy evenings.
Room to grow is for servers that will get more players, more mods or a much bigger world over the next few months.
What uses the most memory
View distance and loaded areas: games like Minecraft and Hytale keep every chunk near every player in memory. Doubling the view distance roughly quadruples the area each player loads.
Mods: big modpacks are the most common reason a server runs out of memory.
The world itself: factories in Factorio and Satisfactory, bases and Pals in Palworld, tames in ARK and builds in Rust all stay in memory while the server runs.
RAM is not the only thing that matters
Most game servers do their main work on one CPU core, so a fast modern processor matters as much as memory. Fast NVMe storage makes saves and world loading quick, and good DDoS protection keeps the server online.
If your server lags but has free memory, more RAM will not help. Lower the view or simulation distance, remove heavy mods, or pre-generate the world instead.