How to Verify Lithium Mod Is Actually Improving Your Performance

Installing Lithium and assuming it works is not the same as confirming it. Because the mod is invisible in normal play, you need a way to measure before and after.

Setting Up a Baseline

Before trusting any numbers, create a controlled test. Load a singleplayer world in a consistent location — ideally somewhere with activity like a mob farm or a redstone build. Stand still, do not move the camera, and let the world settle. Open the debug screen with F3 and watch the frame rate and the tick time readings for a minute or two. Write down the range you see. Close the game.

Comparing With and Without the Mod

Now remove Lithium from the mods folder and repeat the exact same test in the same spot. Compare the two sets of numbers. The difference is your real gain. On servers, the relevant metric is tick time rather than FPS — a lower and more stable tick time means the server is keeping up better under load. Remember that results depend heavily on your hardware and what else is running. A world packed with entities and redstone will show a larger improvement than an empty superflat world. If you see no difference at all, check that Lithium is actually listed in your mods screen, because a silently failed load looks identical to a mod that does nothing.