Can GPT-OSS 20B run on ROG Phone 9 Pro?

YESRuns great
Grade S · 100/100 · formula estimate

What this means

Our estimate says GPT-OSS 20B should fit comfortably on your ROG Phone 9 Pro.

Download the MXFP4 version, which is about 12.1 GB. We expect it to use about 14.8 GB of the roughly 20 GB available to a model on this phone.

At the estimated speed, a roughly 300-word answer may take about 24 seconds to finish.

This result is calculated from the phone and model specifications. It has not been measured on this exact phone and setup.

16.7tokens/s
estimated · instant
14.8GB
needed at MXFP4
MXFP4
quant checked
S
grade · 100/100
needs 14.8 GBusable 20 GB
Snapdragon 8 Elite24 GB RAMCPU / GPUalso sold with 16 GB

See how fast it feels

Estimated at 16.7 tokens/s — instant. A ~300-word reply takes about 24 seconds on this phone.

Live demo · 16.7 tokens/s

Where the memory goes

ComponentDetailGB
Model weightsMXFP4 GGUF (12.1 GB) + mmap overhead12.7
KV cache4K context window1.5
Runtimellama.cpp + app overhead0.6
Total neededat MXFP4, 4K context14.8
Usable on ROG Phone 9 Pro24 GB RAM − Android system reserve20
Headroomleft for the OS and your other apps5.2

Pick your quant

QuantDownloadVerdictSpeed
MXFP4 BEST HERE12.1 GB Runs great~16.7 tokens/s

Get it running in 3 steps

1
Install PocketPal from the Play Store — free, no account needed.
2
Download "GPT-OSS 20B MXFP4" in the in-app model hub — 12.1 GB, use Wi-Fi. Search Hugging Face for ggml-org/gpt-oss-20b-GGUF and pick the MXFP4 file.
3
Set context to 4K — expect ~16.7 tokens/s on this phone.

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GPT-OSS 20B ON OTHER PHONES
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