Will It Run AI

Can Command R+ 104B run on Mac Studio M3 Ultra 256GB?

YES — Runs Great

B63Good
Estimated from fit model

Command R+ 104B needs ~95.4 GB VRAM. Mac Studio M3 Ultra 256GB has 184.3 GB. With Q4_K_M quantization, expect ~10 tok/s.

Runtime: llama.cppCapacity: RoomyBandwidth: HighStack: StandardBottleneck: Balanced
Share:

Operating mode

Choose the run profile you care about

Interactive favors responsiveness, while light API and scale-out lean harder on serving readiness. The fit stays the same, but the recommendation lens changes.

Current mode

Balanced

Balanced for general local use. Keeps the ranking neutral across personal and serving workflows.

Capabilities:

Select quantization to explore

Q4_K_M (Medium quality) 95.4 GB, 9.5 tok/s, Runs well
95.4 GB required184.3 GB available
52% VRAM used

Fit status

Runs well

Decode

9.5 tok/s

TTFT

20279 ms

Safe context

131K

Memory

95.4 GB / 184.3 GB

Memory breakdown

Weights63.4 GB
KV Cache3.4 GB
Runtime0.9 GB
Headroom27.6 GB

See how fast it feels

See how fast it feelsCommand R+ 104B on Mac Studio M3 Ultra 256GB
1st promptCold start — includes initialization
>Solve: If a train travels at 60 mph for 2.5 hours, how far does it go?
Let me work through this step by step. Given information: - Speed = 60 mph (miles per hour) - Time = 2.5 hours Formula: Distance = Speed x Time Calculation: Distance = 60 mph x 2.5 h = 150 miles The train travels 150 miles. Double-check: at 60 mph the train covers 60 miles each hour. In half an hour it covers 30 miles. So in 2.5 hours: 60 + 60 + 30 = 150 miles. Confirmed.
2nd promptWarm — model ready, no init overhead
>What if the train stops for 20 minutes halfway?
The stop doesn't change the total distance covered while moving, but it affects total trip time. Breakdown: - First half: 1.25 hours at 60 mph = 75 miles - Stop: 20 minutes (no distance) - Second half: 1.25 hours at 60 mph = 75 miles Total distance: 150 miles (same) Total time: 2.5 h + 0.33 h = 2.83 hours Average speed: 150 / 2.83 = 53 mph The distance stays the same but average speed drops to 53 mph because of the stop.
Estimated: 9.5 tok/s decode · 20.3s TTFT (warm) · 24 tok/s prefill

What limits this setup

This setup is broadly balanced for this model.

Shared-memory contention still exists

The OS, browser, and inference runtime all compete for the same physical memory pool, so real-world headroom is less forgiving than raw capacity suggests.

Best improvement path

Performance by workload

WorkloadGradeFitDecodeTTFTContext
ChatBRuns well9.5 tok/s11061 ms131K
CodingBRuns well9.5 tok/s20279 ms131K
Agentic CodingBRuns well9.5 tok/s29497 ms131K
ReasoningBRuns well9.5 tok/s23966 ms131K
RAGBRuns well9.5 tok/s36871 ms131K

Quantization options

How Command R+ 104B (104B params) fits at each quantization level on Mac Studio M3 Ultra 256GB (184.3 GB usable).

QuantBitsVRAMQualityFit
Q2_K
2
40.6 GB
LowB58
Q3_K_S
3
51.0 GB
LowB59
NVFP4
4
58.2 GB
MediumB60
Q4_K_M
4
63.4 GB
MediumB60
Q5_K_M
5
74.9 GB
HighB62
Q6_K
6
85.3 GB
HighB63
Q8_0Best for your GPU
8
111.3 GB
Very HighB65
F16
16
213.2 GB
MaximumF0

Get started

Copy-paste commands to run Command R+ 104B on your machine.

Run

ollama run command-r-plus

Opciones de mejora

Hardware que ejecuta bien Command R+ 104B

Frequently asked questions

Can Mac Studio M3 Ultra 256GB run Command R+ 104B?

Yes, Mac Studio M3 Ultra 256GB can run Command R+ 104B with a B grade (Runs well). Expected decode speed: 9.5 tok/s.

How much VRAM does Command R+ 104B need?

Command R+ 104B (104B parameters) requires approximately 95.4 GB of memory with Q4_K_M quantization.

What is the best quantization for Command R+ 104B?

The recommended quantization for Command R+ 104B is Q4_K_M, which balances quality and memory efficiency.

What speed will Command R+ 104B run at on Mac Studio M3 Ultra 256GB?

On Mac Studio M3 Ultra 256GB, Command R+ 104B achieves approximately 9.5 tokens per second decode speed with a time-to-first-token of 20279ms using Q4_K_M quantization.

Can Mac Studio M3 Ultra 256GB run Command R+ 104B for coding?

For coding workloads, Command R+ 104B on Mac Studio M3 Ultra 256GB receives a B grade with 9.5 tok/s and 131K context.

What context window can Command R+ 104B use on Mac Studio M3 Ultra 256GB?

On Mac Studio M3 Ultra 256GB, Command R+ 104B can safely use up to 131K tokens of context. The model's official context limit is 131K, but available memory constrains the safe maximum.

Is unified memory on Mac Studio M3 Ultra 256GB as fast as VRAM for Command R+ 104B?

Not always. Mac Studio M3 Ultra 256GB can often fit larger models thanks to unified memory, but a discrete GPU with dedicated high-bandwidth VRAM may still decode faster once the model fits. For this combination, the important distinction is capacity versus sustained throughput.

See all results for Mac Studio M3 Ultra 256GBSee all hardware for Command R+ 104B
Embed this result

Paste this snippet into any page to show a live fit card.

<iframe src="https://willitrunai.com/embed/command-r-plus-104b-on-m3-ultra-256gb" width="400" height="180" frameborder="0" style="border:none;border-radius:12px;overflow:hidden;" title="Will It Run AI — fit result"></iframe>

Preview: