Anti-cheat plugins detect movement, combat, and interaction patterns that indicate hacked clients, fly, speed, killaura, reach, and similar, and they matter far more once a server is open to the public than on a small trusted friend group where cheating is unlikely to begin with.
Grim (free, open source)
Grim is widely regarded as the best free anti-cheat available, and it is genuinely competitive with paid options. It runs entirely server-side (no client mod needed), uses predictive movement simulation to catch a wide range of movement and combat cheats, and is built to run its checks off the main server thread to minimize performance impact. It supports Minecraft versions from 1.8 through current releases and works across Paper, Spigot, and Folia.
Vulcan (paid)
Vulcan is one of the most widely used paid anti-cheats, with an in-game GUI, straightforward configuration, and strong detection for reach, killaura, and fly hacks specifically. It is a common pick for mid-to-large servers that want a more polished management interface than a free option typically offers.
Spartan (paid)
Spartan is another established paid option, covering a broad range of hack types along with additional features like anti-bot and basic anti-X-ray detection bundled in.
Matrix
Matrix is a longer-standing name in the anti-cheat space, mentioned alongside Grim and Vulcan as a solid option, particularly for servers already invested in its specific configuration ecosystem.
Do you actually need one?
For a small server with a trusted friend group, an anti-cheat is genuinely optional, the people playing are unlikely to cheat against each other, and the plugin is one more thing to configure and tune for false positives. Once a server opens to the public, especially anything competitive (PvP, minigames, ranked survival), an anti-cheat moves from optional to close to essential, public servers attract cheaters at a scale a small SMP simply never sees.
Configuration matters as much as the choice
Every anti-cheat on this list requires some tuning to your specific server's expected playstyle, an aggressive PvP server needs different sensitivity than a calm survival build server, to avoid false-flagging legitimate players. Read each plugin's configuration documentation before assuming default settings are correctly tuned for your community.
Getting a server that can handle the load
Anti-cheat plugins add ongoing per-player processing overhead, so a server intended to run one, especially on a busy public PvP server, benefits from headroom beyond the bare minimum. A RAM calculator can help size a plan correctly. Tick Hosting's plans give you that headroom starting with a free tier. Get started on Tick Hosting's plans page.