Gemma 4 12B is a 11.96B-parameter model. At Q4_K_M it needs about 7.9 GB of memory. The Mac Studio M3 Ultra 512GB has 384 GB usable, so it fits entirely in memory. Expect about 61 tokens/sec (35–88), with the first token after 0.4 s for a short prompt. This estimate is interpolated from benchmarks of similar setups.
| Quantization | File size | Memory | Generation | First token | Source |
|---|---|---|---|---|---|
| Q4_K_M | 7.1 GB | Fits | 61 tok/s | 0.4 s | Derived |
| Q8_0 | 12.7 GB | Fits | 35 tok/s | 0.4 s | Derived |
| FP16 | 23.8 GB | Fits | 18 tok/s | 0.4 s | Derived |
All models on the Mac Studio M3 Ultra 512GB · 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.