Gemma on Apple M3
Can I run Gemma 3 12B on an Mac Studio M3 Ultra 256GB?
Yes. Gemma 3 12B at Q4_K_M uses 8.3 GB of the 192.0 GB available on a Mac Studio M3 Ultra 256GB, and runs at about 61.8 tokens per second. You can push the context to 128K.
Runs comfortably
8.3 GB of 192.0 GB · 4%0192 GB
Weights
7.0 GB
KV cache
0.8 GB
Runtime overhead
0.5 GB
Gemma 3 12B at Q4_K_M leaves 183.7 GB spare on a Mac Studio M3 Ultra 256GB. There is room to raise the context length or move up a quantisation level.
Generation61.8tok/s
Prompt processing981tok/s
Max context128Ktokens
KV per 1K tokens0GB
Every quantisation of Gemma 3 12B on a Mac Studio M3 Ultra 256GB
Highlighted row is the highest quality that still fits at 8K context.
| Quantisation | bpw | Weights | Total | Verdict | Max ctx | tok/s |
|---|---|---|---|---|---|---|
| FP16 / BF16 | 16.00 | 22.7 GB | 24.1 GB | Runs comfortably | 128K | 20.2 |
| INT8 / W8A8 | 8.50 | 11.8 GB | 13.2 GB | Runs comfortably | 128K | 37.7 |
| Q8_0 (GGUF) | 8.50 | 11.8 GB | 13.2 GB | Runs comfortably | 128K | 37.7 |
| FP8 (E4M3) | 8.00 | 11.4 GB | 12.7 GB | Runs comfortably | 128K | 39.2 |
| Q6_K | 6.56 | 9.3 GB | 10.6 GB | Runs comfortably | 128K | 47.2 |
| Q5_K_M | 5.67 | 8.1 GB | 9.4 GB | Runs comfortably | 128K | 54.1 |
| Q5_K_S | 5.52 | 7.8 GB | 9.2 GB | Runs comfortably | 128K | 55.4 |
| AWQ 4-bit | 4.25 | 7.4 GB | 8.7 GB | Runs comfortably | 128K | 58.3 |
| GPTQ 4-bit | 4.25 | 7.4 GB | 8.7 GB | Runs comfortably | 128K | 58.3 |
| MXFP4 | 4.25 | 7.4 GB | 8.7 GB | Runs comfortably | 128K | 58.3 |
| Q4_K_M | 4.85 | 7.0 GB | 8.3 GB | Runs comfortably | 128K | 61.8 |
| Q4_K_S | 4.58 | 6.6 GB | 7.9 GB | Runs comfortably | 128K | 64.7 |
| Q4_0 | 4.55 | 6.6 GB | 7.9 GB | Runs comfortably | 128K | 65.1 |
| IQ4_XS | 4.25 | 6.2 GB | 7.5 GB | Runs comfortably | 128K | 68.8 |
| Q3_K_M | 3.91 | 5.7 GB | 7.1 GB | Runs comfortably | 128K | 73.5 |
| IQ3_M | 3.70 | 5.5 GB | 6.8 GB | Runs comfortably | 128K | 76.8 |
| IQ3_XXS | 3.06 | 4.6 GB | 6.0 GB | Runs comfortably | 128K | 88.8 |
| Q2_K | 2.63 | 4.1 GB | 5.4 GB | Runs comfortably | 128K | 99.2 |
| IQ2_XXS | 2.06 | 3.3 GB | 4.7 GB | Runs comfortably | 128K | 117 |
| IQ1_M | 1.75 | 2.9 GB | 4.3 GB | Runs comfortably | 128K | 131 |