How to run OpenAI's new gpt-oss-20b LLM on your computer

Hands On Earlier this week, OpenAI released two popular open-weight models, both named gpt-oss. Because you can download them, you can run them locally.

The lighter model, gpt-oss-20b, has 21 billion parameters and requires about 16GB of free memory. The heavier model, gpt-oss-120b, has 117 billion parameters and needs 80GB of memory to run. By way of comparison, a frontier model like DeepSeek R1 has 671 billion parameters and needs about ~875GBs to run, which is why LLM developers and their partners are building massive datacenters as fast as they can.

Unless you're running a high-end AI server, you probably can't deploy gpt-oss-120b on your home system, but a lot of folks have the memory necessary to work with gpt-oss-20b. Your computer needs either a GPU with at least 16GB of dedicated VRAM, or 24GB or more system memory (leaving at least 8GB for the OS and software ...