LagLens

A simple and intuitive in-game profiler that helps you instantly find the exact sources of lag on your server or in your world.

What it does

This mod visualizes performance impact directly in-game using a real-time heatmap. Blocks, entities, and mechanisms are highlighted from green (low impact) to red (high impact), making it easy to spot what is causing FPS or TPS drops.

Key Features

Real-time heatmap overlay (toggle with a single key)
Highlights blocks, entities, and machines based on performance cost
Displays tick time usage (in microseconds) above objects
Works directly in the world — no external tools or web dashboards needed
Quickly identify laggy farms, mob systems, or automation setups

Why use this?

Traditional tools like Spark or Observable provide complex logs and dashboards, which can be hard to interpret quickly. This mod brings all the important information directly into the game world, allowing both players and server admins to diagnose and fix lag in seconds.

Use Cases

Finding laggy mob farms
Detecting inefficient redstone or tech setups
Debugging server performance issues
Optimizing large bases or modded systems

How to use

Press the assigned key (configurable) to enable the overlay. Look around your world — the most performance-heavy elements will immediately stand out.

Make your world smoother, faster, and easier to debug — right from inside the game.