Can You Run Gemma 4 on a Mac Studio (128GB)?
Yes — best fit is Gemma 4 31B at BF16 (16-bit) (~58.3GB) ✅ Comfortable, using 123GB of usable memory on a 128GB Mac Studio.
Every Gemma 4 model on this configuration
| Model | Best quant | Size | Status |
|---|---|---|---|
| Gemma 4 E2B | BF16 (16-bit) | ~8 GB | ✅ Comfortable |
| Gemma 4 E4B | BF16 (16-bit) | ~15 GB | ✅ Comfortable |
| Gemma 4 12B | BF16 (16-bit) | ~26.7 GB | ✅ Comfortable |
| Gemma 4 26B A4B | BF16 (16-bit) | ~48 GB | ✅ Comfortable |
| Gemma 4 31B | BF16 (16-bit) | ~58.3 GB | ✅ Comfortable |
How we got this verdict
128 - 5 = 123GB usable (macOS and background processes reserve roughly 5 GB of unified memory).
Because Mac Studio has enough unified memory to spare, 31B fits at BF16 (16-bit)— a higher-precision quant than most setups get. You don't need the 4-bit QAT build here, though it's still a safe download if you want a smaller file for a second model running alongside it.
Real-world notes for this configuration
128GB is well into Ultra-chip territory on the Mac Studio, and at this tier every current Gemma 4 model fits, including the 31B flagship at full BF16 precision (58.3GB). This is the same maximum ceiling the MacBook Pro's top configuration offers, but here it typically comes with the Ultra chip class, which the MacBook Pro doesn't offer at all.
- ⚠At this memory and chip tier, you're paying for headroom well beyond the current Gemma 4 lineup's needs — worth confirming this is genuinely the workload you need before over-buying.
Try a different configuration
Best fit: Gemma 4 31B · BF16 (16-bit) · ~58.3 GB ✅ Comfortable
FAQ
Can a Mac Studio (128GB) run the 31B flagship model?
Yes, comfortably — Gemma 4 31B fits at BF16 (16-bit) (~58.3GB), using 123GB of usable memory on this configuration.
What's the best Gemma 4 model for a Mac Studio (128GB)?
Gemma 4 31B at BF16 (16-bit) (~58.3GB) is the best fit — it's the largest model that runs comfortably within the 123GB of usable memory here.
What if I have more or less memory than 128GB?
This is the top configuration in this family — every Gemma 4 model already fits at its best available quant. With less (e.g. 96GB), the best-fitting model gets smaller or tighter — see the Mac Studio page.
Is 128GB on a Mac Studio the same chip as 128GB on a MacBook Pro?
Not necessarily — the MacBook Pro's 128GB configuration uses the Max chip, while a Mac Studio at 128GB is often running the Ultra chip, which has meaningfully higher memory bandwidth despite the capacity being the same number.
Does 128GB run every Gemma 4 model at full precision?
See this page's model table above — at this usable-memory tier, even the 31B flagship's full BF16 weights (58.3GB) fit, which is the highest-precision, largest-memory-footprint configuration in the entire current lineup.