Paper, Spigot, Purpur, Fabric: which software for your server?

The "jar" you run decides almost everything: what you can install (plugins or mods), performance, and the settings available. The good news: for the vast majority of servers, the answer is simple.

The short answer

• A server with plugins (survival, factions, skyblock, minigames): Paper.
• A modded server (Create, modpacks): NeoForge or Fabric, depending on the mods you want.
• A pure vanilla server among friends: the official server, or Fabric with optimisation mods.

The two families

Plugin servers (Bukkit, Spigot, Paper, Purpur) add features on the server side only: players connect with normal Minecraft. It's the path of almost every public server.

Modded servers (Fabric, Forge, NeoForge) add blocks, items, worlds: every player has to install the same mods. See Set up a modded server.

The two don't mix natively: a plugin doesn't run on Fabric, a mod doesn't run on Paper.

Plugin servers, up close

Software	In short
Vanilla	Mojang's official server: no plugins
Spigot	Bukkit's heir; the base of the plugin ecosystem
Paper	a Spigot fork: much faster, fixes many bugs, compatible with Spigot plugins
Purpur	a Paper fork: hundreds of extra gameplay settings
Folia	a Paper fork, multi-core by regions; most plugins aren't compatible

Paper is the default choice: Spigot and Bukkit plugins work, performance is clearly better, and it's what most recent plugins target (some only work on Paper, in fact).

Purpur is worth a look if you want to tune specific mechanics (riding certain mobs, adjusting behaviours) without an extra plugin. It stays compatible with Paper plugins.

Folia splits the world into regions handled by several cores. It's for very large servers that have hit the limits of a single core, and needs plugins written for it: it's not a starting choice.

Modded servers

• Fabric: light, updated very quickly after each Minecraft version. It also works for an "optimised vanilla" server with server-side-only mods, like Lithium, without players having anything to install.
• NeoForge: Forge's successor for recent versions, where many big mods and modpacks live.
• Forge: still around for older versions and the modpacks that depend on them.

The modpack you pick decides for you: it states which loader it runs on.

Hybrids, to avoid

Some software promises plugins and mods on the same server. They exist, but incompatibilities are frequent, updates lag behind and bugs are hard to diagnose. For a public server, choose one family.

Changing software

• Vanilla or Spigot to Paper: replace the jar, the world and plugins are kept. Make a backup first, as for an update.
• Paper to Purpur: same principle, no risk for plugins.
• Plugins to mods (or the reverse): it's not a migration, it's a new server.

Once the software is chosen, check the Java version it needs, generate the launch command with the Startup flags & RAM tool, and tune performance with the anti-lag configuration, which covers Paper, Purpur and Velocity.