text model · gpt-oss · iOS
Can I run gpt-oss 20B on iPad Pro M4 (16GB, 1TB/2TB config)?
No. gpt-oss 20B needs ~13.2 GB even at Q4_K_M, but iPad Pro M4 (16GB, 1TB/2TB config) only has ~12 GB usable.
Needs ~13.2 GB even at Q4_K_M, but only ~12 GB is usable.
That figure is at a 4k context and moves about ±15% as context length changes.
The gap is about 1.2 GB: gpt-oss 20B needs roughly 13.2 GB at Q4_K_M and iPad Pro M4 (16GB, 1TB/2TB config) leaves only about 12 GB usable for a model. The lightest tracked hardware that runs gpt-oss 20B is the Nvidia GeForce RTX 4060 Ti (16GB) at 16 GB. See gpt-oss 20B on Nvidia GeForce RTX 4060 Ti (16GB).
- Q4_K_M needed
- ~13.2 GB
- Usable on device
- ~12 GB
- Device memory
- 16 GB
Which quant fits
How to run it
On iOS use Apple Foundation Models (Built into iOS 26, ~3B on-device model, zero download, fully private.).
- Parameters
- 21B (MoE, 3.6B active)
- Q4_K_M size
- 11.28 GB
- Q8_0 size
- 0.86 GB
- Context
- 128k
- Ollama tag
- gpt-oss:20b
- Memory
- 16 GB unified
- Usable for weights
- ~12 GB
- Power draw
- ~14 W
- Best runtime
- MLX (via Python or Swift; mlx-lm package)
What you can run instead
Run gpt-oss 20B on other hardware
FAQ
Can iPad Pro M4 (16GB, 1TB/2TB config) run gpt-oss 20B?
No. gpt-oss 20B needs ~13.2 GB even at Q4_K_M, but iPad Pro M4 (16GB, 1TB/2TB config) only has ~12 GB usable.
How much memory does gpt-oss 20B need?
iPad Pro M4 (16GB, 1TB/2TB config) does not have enough memory. At Q4_K_M the weights are ~11.28 GB; with KV cache and runtime overhead, budget ~13.2 GB at a 4k context. It is a Mixture-of-Experts model (21B total / 3.6B active), so all experts must stay in memory; memory tracks total params, not active params.
What is the best tool to run gpt-oss 20B on iOS?
On iPhone and iPad, Apple Foundation Models (Built into iOS 26, ~3B on-device model, zero download, fully private.) is the standard choice. Phones realistically run 1B-4B class models. Anything larger thermally throttles or OOMs.
Embed this
A live badge for your model card or README, updated as the data is. [](https://localmodel.run/can-i-run/gpt-oss-20b/ipad-pro-m4-16gb) Sources
- apple.com/ipad-pro
- apple.com/newsroom
- developer.apple.com
- enclaveai.app
- github.com/a-ghorbani
- github.com/google-ai-edge
- github.com/mainframecomputer
- gsmarena.com
- huggingface.co/ggml-org
- huggingface.co/openai
- layla-network.ai
- ollama.com/library/gpt-oss
- ollama.com/library/gpt-oss/tags
- phonearena.com
- privatellm.app
- support.apple.com/en-us/119891
- support.apple.com/en-us/119892
Weights are measured from GGUF files; KV cache and overhead are computed, so totals can vary ~15% with context and runtime. Any tok/s is a bandwidth estimate. See methodology.