Can I Run Cosmos 3 on Mac Studio (M3 Ultra, 256 GB)?

Written by Jakub Rusinowski · Last updated July 21, 2026

Yes — comfortably

Yes, comfortably — Cosmos 3 Super at Q8_0 needs about 71.1 GB of the 192 GB usable on Mac Studio (M3 Ultra, 256 GB), leaving ~120.9 GB spare and running at ~12.3 tok/s (estimated), with room for about 16,384 tokens of context.

Confidence: medium · Recommended quantization: Q8_0 · Estimated speed: ~12.3 tok/s

Mac Studio (M3 Ultra, 256 GB) — what it gives a model

Usable memory for models192 GB
Memory bandwidth819 GB/s
Form factorDesktop
Operating systemmacOS
Memory upgradeableNo — soldered

Cosmos 3 on Mac Studio (M3 Ultra, 256 GB): memory by quantization

QuantMemory neededFits 192 GB?Max contextEst. speedDownload
F16131.1 GB✓ Yes16K~6.7 tok/s128 GB
Q8_071.1 GB✓ Yes16K~12.3 tok/s68 GB
Q6_K55.6 GB✓ Yes16K~15.6 tok/s52.5 GB
Q5_K_M48.5 GB✓ Yes16K~17.8 tok/s45.4 GB
Q4_K_M41.8 GB✓ Yes16K~20.6 tok/s38.6 GB
Q3_K_M30.4 GB✓ Yes16K~27.8 tok/s27.3 GB
Q2_K24.2 GB✓ Yes16K~34.5 tok/s21 GB

Which Cosmos 3 sizes fit

VariantNeeds at Q4_K_MFits?Est. speed
Cosmos 3 Super41.8 GB✓ Fits~20.6 tok/s
Cosmos 3 Nano11.9 GB✓ Fits~65.1 tok/s
Cosmos 3 Edge4.1 GB✓ Fits~149.3 tok/s

What to watch out for

Mac Studio M3 Ultra 256 GB limitations

Recommended setup

Ollama or LM Studio (Metal) — MLX for the fastest Apple-native throughput

How these numbers are calculated

FAQ

Can I run Cosmos 3 on Mac Studio (M3 Ultra, 256 GB)?

Yes, comfortably — Cosmos 3 Super at Q8_0 needs about 71.1 GB of the 192 GB usable on Mac Studio (M3 Ultra, 256 GB), leaving ~120.9 GB spare and running at ~12.3 tok/s (estimated), with room for about 16,384 tokens of context.

Which quantization of Cosmos 3 should I use on Mac Studio (M3 Ultra, 256 GB)?

Q8_0 — it needs about 71.1 GB of the 192 GB available, downloads as roughly 68 GB, and runs at an estimated 12.3 tokens/sec with up to 16K of context.

What limits Cosmos 3 on Mac Studio (M3 Ultra, 256 GB)?

Nothing binding — the model fits with headroom and generates at a usable speed on this hardware.

Which runtime should I use?

Ollama or LM Studio (Metal) — MLX for the fastest Apple-native throughput

Other Computers

Other Models on Mac Studio (M3 Ultra, 256 GB)

Cosmos 3 on GPUs

What This Model Is Good At

Model & Tools

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