GPT-OSS 120B

In non-nerd speak

Who makes it: OpenAI. The files come from the maker's own Hugging Face account.

License: Apache License 2.0. A standard open source license. You can use, change, and share it, even to make money. Keep the license notice.

Business use: Yes. Business use is allowed. Keep the license and notice files when you share it.

Training data: We have not found a full public data release. Not yet checked in depth.

Will it run on my computer?

Pick a computer with at least 128 GB of memory. On a Mac, that is the unified memory. On a PC, a graphics card with that much VRAM is fastest. A PC with only normal RAM will also work, just slower. This model uses a mix of experts. Only part of it works on each word, so it runs faster than its size suggests.

Not sure? Use our pick-by-computer guide.

How to run it in LM Studio

1. Get LM Studio from lmstudio.ai and open it.
2. Open the Discover tab. Search for lmstudio-community/gpt-oss-120b-GGUF.
3. Pick a file that ends in Q4_K_M. It is the best mix of size and quality for most people.
4. Click Download. When it is done, open a new chat and load the model.

The files are GGUF builds that LM Studio can load. We checked that this repo exists on Oct 14, 2026. Full LM Studio guide.

How to use it with Hermes

Does it fit? Yes. Its memory window is big enough for Hermes.

1. Load the model in LM Studio. Set the context length to at least 64000.
2. In LM Studio, open the Developer tab and start the server.
3. In a terminal, run hermes model. Choose LM Studio and press Enter to keep http://localhost:1234/v1.
4. Pick this model from the list. Then run hermes to start.

Steps based on the Hermes docs. Full Hermes guide.

Common questions

Is GPT-OSS 120B truly open source?

Yes, OSI-approved license. A standard open source license. You can use, change, and share it, even to make money. Keep the license notice.

Can I use GPT-OSS 120B for my business?

Yes. Business use is allowed. Keep the license and notice files when you share it.

Do I need to sign up to download GPT-OSS 120B?

No. Download without an account.

How much memory does GPT-OSS 120B need?

Our estimate is about 87 GB of RAM for a 4-bit file of about 70.1 GB. This is a rough guide, not a test.

Sources we checked

If the maker's page and this page disagree, trust the maker. Tell us what we got wrong.