Twoody
Local LLM calculator
The best local LLM for your iMac
From the M1 to the M4, with 8 to 32 GB: the strongest model that runs comfortably on each iMac, and how fast it writes.
| Your computer | Memory | Recommended — runs comfortably | Writes | One click in Twoody |
|---|---|---|---|---|
M4 — MacBook Air, MacBook Pro, Mac mini, iMac |
16 GB | Llama 3.1 8B | 15–22 tokens/s | Qwen3.5 9B |
| 24 GB | gpt-oss-20b | 25–36 tokens/s | Qwen3.5 9B | |
| 32 GB | GLM-4.7-Flash | 32–46 tokens/s | Qwen3.5 9B | |
M3 — MacBook Air, MacBook Pro, iMac |
8 GB | Llama 3.2 3B | 31–45 tokens/s | Qwen3.5 4B |
| 16 GB | Llama 3.1 8B | 13–19 tokens/s | Qwen3.5 9B | |
| 24 GB | gpt-oss-20b | 23–32 tokens/s | Qwen3.5 9B | |
M1 — MacBook Air, MacBook Pro, Mac mini, iMac |
8 GB | Llama 3.2 3B | 20–29 tokens/s | Qwen3.5 4B |
| 16 GB | Llama 3.1 8B | 8.9–13 tokens/s | Qwen3.5 9B |
Estimates, not measurements, computed from public llama.cpp benchmarks. Figures reviewed on September 26, 2026.
An iMac with 8 GB runs models of about 4 billion parameters; with 16 or 24 GB, 8 to 14 billion — enough for writing and for questions about your documents.
The M3 and M4 write and read faster than the M1 with the same model; the memory decides which models fit.
On a desk all day, an iMac is also a good computer for the iPhone and Android apps, in private beta, to use from afar.
Questions about running an LLM locally
Which LLM for an iMac with M4?
With 16 GB, Qwen3.5 9B; with 24 or 32 GB, Qwen3 14B or a mixture of experts such as gpt-oss-20b. Twoody installs the Qwen3.5 that suits its memory.
Can an iMac with 8 GB run a local LLM?
Yes, a model of about 4 billion parameters such as Qwen3.5 4B, which Twoody installs, enough for emails and summaries.
And an Intel iMac?
Twoody runs on Intel iMacs with macOS 13 or later; the model runs on the processor, more slowly. See the page on Intel Macs.
The best local LLM, by computer
Twoody is in private beta.
On Mac, Windows and Linux, free, with no account and no subscription — and on iPhone and Android, with Twoody on your computer. Leave your email: we will write to you when Twoody opens to you.