By Peter · ModelFit · 2026-08-28

Best LLM for Mac Studio M5 Max with 48GB RAM (2026)

The 48GB Mac Studio M5 Max is the MoE sweet spot of the lineup. At 48GB with the full 614 GB/s memory bus, it unlocks the 35B MoE class with real context headroom. It starts at $2,499 for the base chip, and the 40-core GPU variant at $3,099 keeps the same memory. This is the machine for developers and researchers who want fast MoE inference without paying for dense 70B memory or the M5 Ultra's higher entry price.

TL;DR: The 48GB M5 Max runs every 35B MoE comfortably. Qwen3.5 35B-A3B Instruct (~70 tok/s est.) and Qwen3.6 35B-A3B (~70 tok/s est.) lead on quality. Laguna XS 2.1 (~72 tok/s est.) is the fastest for agentic coding. Qwen3 30B (~75 tok/s est.) is the speed king. Ornith 1.0 35B (~20 tok/s est.) adds dense 35B capability.
Bar chart of estimated tokens per second for top LLMs on a Mac Studio M5 Max 48GB at Q4_K_M Estimated token generation on the Mac Studio M5 Max 48GB. ModelFit engine estimates.

The Mac Studio device page covers the full hardware comparison. This guide ranks the models that shine at 48GB and the ones that need more memory.

How 48GB Shapes Your Model Choices

With 48GB of unified memory, your usable budget climbs well above the 36GB tier. The full 614 GB/s bus also removes the bandwidth bottleneck of the binned entry config.

AllocationSize
macOS + system services~8-9 GB
Available for LLM~35 GB
...with browser and editor open~30-32 GB

At Q4_K_M, a 35B dense model loads ~21GB, and a 35B MoE loads ~20-22GB. That leaves 10-15GB for KV-cache, which is enough for 32K-64K context on MoE models. The math is straightforward: 48GB is the first tier where 35B MoE models feel roomy rather than tight.

The 614 GB/s bus (vs 460 GB/s on the 36GB config) adds roughly 33% more bandwidth. In tok/s terms, every model on this tier runs faster than it would on the binned memory, and MoE models with small active parameters see the largest relative gain.

This is also the first tier where you can run two smaller models side by side. A Qwen3.5 35B-A3B and a Gemma 4 26B sit in memory together for multi-agent or hybrid workflows.

Best Models Ranked

RankModelTypeSizeEst. tok/sBest for
1Qwen3.5 35B-A3B InstructMoE (3B active)Q4_K_M ~20GB~70 est.Reasoning, coding, agent scenarios
2Qwen3.6 35B-A3BMoE (3B active)Q4_K_M ~22GB~70 est.Reasoning, coding, agents
3Qwen3.6 27BDenseQ4_K_M ~18GB~26 est.Coding, quality, long context
4Laguna XS 2.1MoE (3B active)Q4_K_M ~20.3GB~72 est.Agentic coding, long-horizon tasks
5Ornith 1.0 35BDenseQ4_K_M ~21.2GB~20 est.Agentic coding
6Qwen3 30BMoE (3B active)Q4_K_M ~22GB~75 est.Quality, coding

Model Details

1. Qwen3.5 35B-A3B Instruct is the top all-rounder for 48GB. At ~20GB loaded, it leaves 10-12GB for context and system overhead. Its ~70 tok/s est. decode speed makes it a viable daily driver for chat, coding, and reasoning tasks. The Alibaba team trained it to handle complex instructions on par with 70B-class models on many reasoning benchmarks, and the small active MoE keeps inference fast.

ollama run qwen3.5:35b-a3b

2. Qwen3.6 35B-A3B is the newer sibling. It loads ~22GB, slightly heavier than the 3.5, but the quality lift shows on agentic coding and structured output. Expect ~70 tok/s est., matching the 3.5 on decode speed.

ollama run qwen3.6:35b-a3b

3. Qwen3.6 27B is the flagship dense model for this tier. At ~18GB, it leaves the most headroom of any pick. Its ~26 tok/s est. is slower than MoE models, but for tasks that benefit from dense attention over full context windows, such as long-document analysis, it is the correct choice.

ollama run qwen3.6:27b

4. Laguna XS 2.1 is a 33B MoE specialized for agentic coding. At ~20.3GB and ~72 tok/s est., it edges the Qwen models on speed by a small margin. Its design emphasizes long-horizon tasks where the agent must maintain reasoning across many tool calls.

ollama run laguna-xs-2.1:q4_K_M

5. Ornith 1.0 35B is the only dense 35B on this list. At ~21.2GB and ~20 tok/s est., it is slower than the MoE picks but delivers full dense quality for coding-agent workflows. It shines in tool-calling scenarios where MoE gating can occasionally route to suboptimal experts.

ollama run ornith:35b

6. Qwen3 30B runs at ~75 tok/s est., the fastest model on this tier. It is an older MoE (3B active) that still delivers strong coding and chat quality. At ~22GB, it fits alongside a browser and editor without pressure.

ollama run qwen3:30b

What 48GB Cant Run

With more capacity, the boundaries shift to Q8 quantization and dense 70B models:

  • Gemma 4 26B-A4B (Q8) needs 28.1GB, which is feasible at 48GB but heavy. Stick with Q4_K_M on this tier.
  • Qwen3.6 27B (Q8) needs 30GB. Same story.
  • Mixtral 8x7B Instruct (46.7B parameters, 30GB at Q4) fits but fills most of your budget with no room for context. Skip it.
  • Qwen3.6 35B-A3B (Q8) needs 38.7GB. That is too tight for 48GB.
  • Qwen3.5 35B-A3B Instruct (Q8) needs 38.7GB. Same limit.

For 70B dense models at Q4, you need at least the 64GB M5 Max. For 120B MoE, jump to the 96GB M5 Max or M5 Ultra.

FAQ

Can the 48GB M5 Max run a 70B model?

No. A 70B model needs roughly 42GB at Q4, which nearly fills your entire budget. The 48GB tier is correct for 35B MoE and 27B dense. For 70B, step up to the 96GB M5 Max or the M5 Ultra.

How does the 48GB M5 Max compare to the 36GB?

The jump is significant. You get the full 614 GB/s bus (vs 460 GB/s) and 35B MoE models fit with real context headroom. The 36GB config handles 27B dense well, but the 48GB opens the 35B MoE class properly.

Is 48GB enough for running two models at once?

Yes, barely. Two 35B MoE models at Q4 each take ~20-22GB, totaling 40-44GB. That leaves 4-8GB for macOS plus KV-cache. Running a 35B MoE alongside a 9B model is more comfortable and does not require aggressive context limits.

What is the best model for coding on the 48GB M5 Max?

Qwen3.5 35B-A3B Instruct for general coding, Laguna XS 2.1 for agentic tool-calling workflows, and Ornith 1.0 35B for dense coding quality when you need it. Each fits comfortably at this tier.

Does the 48GB tier always have the 614 GB/s bus?

Yes. The 460 GB/s bus is specific to the 36GB binned config. All 48GB and higher M5 Max configurations ship with the full 614 GB/s memory bandwidth.

Where to Buy for Local AI

best configs

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