How fast will Gemma 4 12B feel on the Mac Studio M5 Ultra 256GB?

Gemma 4 12B on the Mac Studio M5 Ultra 256GB

Gemma 4 12B is a 11.96B-parameter model. At Q4_K_M it needs about 7.9 GB of memory. The Mac Studio M5 Ultra 256GB has 192 GB usable, so it fits entirely in memory. Expect about 90 tokens/sec (51–129), with the first token after 0.3 s for a short prompt. This estimate is interpolated from benchmarks of similar setups.

Speed by quantization

QuantizationFile sizeMemoryGenerationFirst tokenSource
Q4_K_M7.1 GBFits90 tok/s0.3 sDerived
Q8_012.7 GBFits51 tok/s0.3 sDerived
FP1623.8 GBFits27 tok/s0.3 sDerived

Gemma 4 12B on other hardware

Other models on the Mac Studio M5 Ultra 256GB

All models on the Mac Studio M5 Ultra 256GB · Gemma 4 12B on all hardware

Estimates for a short prompt on a single device. Measured numbers come from community benchmarks (r/LocalLLaMA, localscore.ai and more); others are derived from similar setups or projected from specs. Open source on GitHub.