The best local LLM for a Mac Studio M2 Ultra (128 GB) is Qwen3.8-Flash-Next at 61 tok/s (estimated). With 128 GB of unified memory it runs 65 of the models in the LLMCheck index — from compact options up to 320B-class models. For everyday chat and coding, Qwen3.8-Flash-Next is the sweet spot. Full ranking below.
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Ranked by LLMCheck suitability (capability balanced against speed on the M2 Ultra). Click a model for its full benchmark and setup. Every speed carries its provenance mark: most are index estimates from the memory-bandwidth model, and a filled square is a published measurement — submit a real run →
| # | Model | Size | License | Speed | Capability |
|---|---|---|---|---|---|
| 1 | Qwen3.8-Flash-Next | 125B | Qwen Custom | estimated61 tok/s | 47/50 |
| 2 | KAT-Coder-V2.5 | 35B | Apache 2.0 | estimated130 tok/s | 39/50 |
| 3 | Qwen 3.6-35B-A3B | 35B | Apache 2.0 | estimated138 tok/s | 38/50 |
| 4 | GLM-5.3-Flash | 320B | MIT | estimated23 tok/s | 48/50 |
| 5 | DeepSeek V4 Flash | 284B | MIT | estimated31 tok/s | 47/50 |
| 6 | DeepSeek V4 Flash Vision-Exp | 305B | MIT | estimated31 tok/s | 47/50 |
| 7 | Qwen3.8-27B | 27.8B | Apache 2.0 | estimated39 tok/s | 46/50 |
| 8 | Inkling-Small | 276B | Apache 2.0 | estimated34 tok/s | 46/50 |
| 9 | Nemotron 3.5 Lightning | 30B | OpenMDW | estimated116 tok/s | 36/50 |
| 10 | Gemma 4 26B-A4B | 26B | Apache 2.0 | estimated119 tok/s | 35/50 |
| 11 | Laguna S 2.1 | 118B | OpenMDW | estimated48 tok/s | 43/50 |
| 12 | Qwen 3.6-27B | 27B | Apache 2.0 | estimated38 tok/s | 44/50 |
Showing the top 12 of 65 models that fit in 128 GB. See the full leaderboard or all benchmarks.
The fastest way to get started is Ollama. Install it, then find the top pick for your Mac in its library and copy the exact tag it lists:
Find Qwen3.8-Flash-Next in the Ollama library → · model card on Hugging Face →
Prefer a GUI? LM Studio gives you a one-click download and chat window. For step-by-step help see our Ollama install guide, or open the Qwen3.8-Flash-Next on M2 Ultra benchmark page for exact settings.
The Mac Studio M2 Ultra (128 GB) tops out at GLM-5.3-Flash. Newer Apple Silicon with more unified memory runs larger, smarter models much faster:
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Qwen3.8-Flash-Next (125B, Qwen Custom) is the best all-round pick at 61 tok/s (estimated) on the M2 Ultra. If you want maximum speed, Maple Preview 20B-A1B hits 441 tok/s (estimated); for maximum capability, GLM-5.3-Flash still fits in 128 GB.
About 65 of the 91 models in the LLMCheck leaderboard fit in 128 GB of unified memory, from compact models up to GLM-5.3-Flash (320B).
Yes. A 70B model in Q4 quantization needs roughly 40–44 GB of memory, which fits in 128 GB with headroom for context.
128 GB is plenty for local AI — you can run capable 30B–70B-class models. Because Apple Silicon uses unified memory, that figure is both your system RAM and your VRAM.