How to Fix Shaders Causing Low FPS or Stuttering

Shader packs are far heavier than vanilla rendering, so performance drops are expected — but you can usually recover a playable framerate without giving up shaders entirely.

Tune Settings Inside the Pack

Most packs expose their own options through the shader selection screen. Open Shader Packs, select your pack, and click Shader Options (or the gear/settings icon). Lower shadow resolution, reduce shadow distance, disable volumetric clouds, and turn off features like ambient occlusion or reflections one at a time to find what costs the most. Shadows and volumetrics are usually the biggest offenders.

Adjust Iris and Video Settings

In Video Settings, reduce render distance and turn off fancy graphics options that stack with shader cost. Iris also has its own performance-related toggles in its settings menu — disabling things you do not visually need frees up GPU time.

Match the Pack to Your Hardware

If tuning does not help, the pack itself may simply be too demanding. Try a lighter pack designed for lower-end systems. Stuttering (as opposed to low average FPS) often comes from shader compilation the first time you load — let the world sit for a minute so caches build up before judging performance.