Local AI Advisor

Can Mac mini M5 Pro 24 GB run gpt-oss-120b?

24 GB unified · 307 GB/s memory bandwidth · gpt-oss-120b has 116.8B parameters (5.1B active per token).

Short answer

No. It doesn't fit in memory.

Needs ≈60 GB but only ≈17 GB is available after the OS, other apps and Open WebUI.

Why it doesn’t fit

Even its smallest practical version (MXFP4) needs about 60 GB for the model, its context memory and the runtime. After macOS (≈3.5 GB), a browser with a few tabs (≈3.0 GB) and Open WebUI (≈1.0 GB), Mac mini M5 Pro 24 GB has about 17 GB left, so it’s 44 GB short.

Ways to make it work

  • Close everything else

    Not enough on its own: with every other app closed it’s still about 41 GB short.

  • Pick a smaller model from the same family

  • Get more memory

    You’d want at least 68 GB of memory in total. The machines below are the cheapest that run it comfortably.

  • Check your exact setup

    These pages assume typical settings. A shorter context or a lighter chat app can change the answer.

    Check Mac mini M5 Pro 24 GB

The same applies to every workload we rate (chat, coding questions, coding in a repository, agentic coding and long documents): they all need at least as much memory as chat.

Other models for Mac mini M5 Pro 24 GB

The best-rated models for chat on this machine.

Everything Mac mini M5 Pro 24 GB can run

Cheapest machines for gpt-oss-120b

Hardware rated comfortable or better for chat, lowest price first.

Same chip, other memory: 48 GB, 64 GB

Different tool, context size or workload?

These pages use typical settings. The full check models your exact setup.

Open sourceCheck my exact setup