# Can I run gpt-oss 120B on Apple M5 (32GB)?

> **No, not enough memory.** Needs ~62.4 GB even at Q4_K_M, but only ~21 GB is usable.

Last validated: 2026-06-15.

## Memory math
- gpt-oss 120B: 117B (MoE, 5.1B active); Q4_K_M weighs 59.03 GB on disk.
- At Q4_K_M with a 4k context it needs ~62.4 GB (weights + KV cache + ~0.8 GB runtime overhead, ±15% with context length).
- Apple M5 (32GB): 32 GB unified, ~21 GB usable for model weights.
- Headroom: ~-41.4 GB.

## How to run
Recommended quant: n/a. Best tool on macOS: LM Studio.

```sh
ollama run gpt-oss:120b
```

## Run gpt-oss 120B on other devices
- [Apple M4 Max (128GB)](https://localmodel.run/can-i-run/gpt-oss-120b/apple-m4-max-128gb)
- [Apple M5 Max (128GB)](https://localmodel.run/can-i-run/gpt-oss-120b/apple-m5-max-128gb)
- [Apple M3 Ultra (256GB)](https://localmodel.run/can-i-run/gpt-oss-120b/apple-m3-ultra-256gb)

## Other models that run on Apple M5 (32GB)
- [Qwen2.5 Coder 32B (32B)](https://localmodel.run/can-i-run/qwen2.5-coder-32b/apple-m5-32gb)
- [Granite 4.0 H Small (32B)](https://localmodel.run/can-i-run/granite-4.0-h-small/apple-m5-32gb)
- [Qwen3 30B-A3B (30.5B)](https://localmodel.run/can-i-run/qwen3-30b-a3b/apple-m5-32gb)
- [Gemma 2 27B (27B)](https://localmodel.run/can-i-run/gemma-2-27b/apple-m5-32gb)
- [Gemma 3 27B (27B)](https://localmodel.run/can-i-run/gemma-3-27b/apple-m5-32gb)
- [Mistral Small 3 24B (24B)](https://localmodel.run/can-i-run/mistral-small-3-24b/apple-m5-32gb)

Estimate, not a guarantee. Sources: https://ollama.com/library/gpt-oss, https://ollama.com/library/gpt-oss/tags, https://huggingface.co/ggml-org/gpt-oss-120b-GGUF, https://huggingface.co/openai/gpt-oss-120b.
More: https://localmodel.run/can-i-run/gpt-oss-120b/apple-m5-32gb