Minecraft TPS and lag spikes explained
A healthy Minecraft server does 20 ticks per second (TPS). Each tick is 50 milliseconds of work. If the server takes longer than 50 ms, ticks run late, TPS drops below 20, and everything feels slow: mobs, redstone, block breaking.
The two numbers
- TPS: ticks per second. 20 is perfect; under 18 you notice; under 15 it is bad.
- MSPT: milliseconds per tick. Under 50 is fine. The closer to 50, the less room you have for spikes.
Read them with /tps on Paper, or /spark tps. See our ticks converter for the maths.
Spikes vs constant lag
- Constant low TPS: the server is overloaded the whole time. Too many entities, too many loaded chunks, a heavy plugin, or too little CPU.
- Spikes: short freezes every few minutes. Usually garbage collection (too little or oddly sized memory), autosaves, chunk generation, or a scheduled plugin task.
Fix it in order
- Profile. Run spark while it lags and read which plugin or chunk is expensive.
- Pre-generate the world to remove generation spikes: Chunky.
- Lower view and simulation distance: best settings.
- Cut entities: big farms and item piles.
- Right-size the memory and flags: RAM calculator and Aikar's flags.
Is it the server or the player?
If the player's own game stutters but others are fine, it is their computer or connection. Server lag affects everyone at the same time and shows in /tps.
More: how to fix server lag.