LagLens

The mod draws a lightweight HUD overlay in the game window. Instead of only reporting frames per second, it tracks frame time, shows the 95th-percentile frame time, and detects stutters. Based on those readings, it points to likely sources of slowdown: render lag, memory pressure, network lag, areas dense with entities, chunk loading stutters, and lag tied to menus and GUI screens. The diagnosis uses simple rule-based checks, not a profiler, so it describes likely causes rather than measuring every component.

The HUD can be kept compact or expanded into more detailed modes, resized, and set to show or hide individual elements. Settings are changed in an in-game settings screen. Diagnostic reports stay on the local computer and are exported manually; the mod does not upload data or collect account information. LagLens does not fix lag by itself, and it may suggest other performance mods such as Sodium, FerriteCore and Entity Culling, which are optional. The build targets Minecraft Java Edition 1.21.x running on Fabric. It is client-side only, so servers do not need it, and it is released under the MIT License but is not open source.