BadOptimizations | Micro Fixes That Add Up to Real FPS

If your game already runs smoothly and you want to squeeze out the last few frames, BadOptimizations is aimed squarely at you. It is a client-side collection of micro optimizations, and each one trims a small piece of work the game repeats every tick or every frame. No single change is dramatic on its own. Together they add up to something bigger, which is exactly how the developer describes the project. Around 47 million downloads later, it is still actively maintained.

Lightmap Caching Explained

Lightmap updates are one of the most expensive parts of the client tick. Every tick, the game runs vector math to calculate light values for blocks and the sky, then uploads the finished texture to your GPU. That is a lot of repeated work for something that often has not changed at all. BadOptimizations cancels the update whenever nothing affecting block brightness has changed. Adjust the gamma slider, gain a potion effect that alters brightness or travel to a new dimension, and the cache refreshes as normal. Stay put under the same light, and the whole calculation gets skipped instead.

Debug Renderers That Only Run When Needed

Minecraft ships four debug renderers that can be activated with a debug server. They cover bees, game events, game tests and villager AI. The catch is that the logic behind all four keeps executing even when there is nothing to process. BadOptimizations only runs that logic when debug is enabled and there is real data from the server to handle. If you never open those debug views, the wasted work simply stops happening.

Sky Color Math That Runs Less Often

Sky color gets the same treatment. Every frame, the game runs a cubic color sampler that loops 216 times to factor in surrounding biomes, even when every biome around you is identical or shares the same sky color. The mod only calls that full sampler when you are actually between biomes with different sky colors, and it caches the result for each tick. The rest of the time, a shorter, simpler and faster calculation takes over.

One catch: this optimization is not available in every game version. It applies only up to a certain release, so if you play on something newer, check the official project page before expecting it.

These are the highlights, not the whole list. Every optimization can be switched off individually in the config file, so if one option ever causes trouble you can drop it without losing the rest.

How Much FPS Does BadOptimizations Add?

It depends on your hardware and a bit of luck, as the developer is quick to point out. On their own test PC, an RTX 3060 with an Intel i7 12700 and 4 GB of allocated RAM inside a heavily optimized modpack, the frame range moved from 1926-1955 FPS up to 2008-2023 FPS. That is a solid bump on a rig already pushing nearly two thousand frames. The relative gain grows once on-screen toasts are active. In that scenario the same setup went from 1351-1384 FPS to 1414-1458 FPS. On more modest hardware, skipped work matters even more, since your frame budget is tighter to begin with.

It also plays nicely next to other performance mods. Sodium attacks rendering costs from its own angle, and Lithium speeds up tick logic without changing how vanilla plays. BadOptimizations handles the small repeated client tasks that neither of those touches, so the approaches complement each other.

How to Install BadOptimizations

1. Set up a mod loader first. BadOptimizations ships builds for Fabric, Forge and NeoForge, so use whichever one your setup already runs.
2. Download the file that matches your loader and game version from the official project page. No dependencies are needed, the mod stands alone.
3. Drop the jar into your mods folder.
4. Start the game. It works out of the box with no extra setup.
5. If a specific option ever misbehaves, open the config file and disable just that one.

BadOptimizations FAQ

Is BadOptimizations a client or server mod?

It is client side only. Client side is required and server side is unsupported, so there is nothing to install on a server you play on. All the savings come from work your own game would otherwise repeat.

Can I turn off individual optimizations?

Yes. Every optimization can be disabled separately in the config file, so a single problematic option never forces you to drop the whole mod.

Does BadOptimizations work with other optimization mods?

It has no dependencies, and the developer benchmarks it inside a heavily optimized modpack. If another mod conflicts with a specific option, that conflict can be registered, and BadOptimizations disables only the affected option automatically. Other mods can also use hooks to tell it when the lightmap or sky color cache genuinely needs an update.

Is BadOptimizations still maintained?

Yes. The latest release shipped in September 2026 and development is active.

You can grab the current file from the download table on this page, which pulls live data from the official project page. If you are still putting your setup together, our full mod install guide and lightweight loader walkthrough cover the basics, and Dynamic FPS is a smart next pick for trimming background load.