gpt-oss-20b is OpenAI's smaller open-weight model, designed for lower latency and local or specialized use cases, with MXFP4 quantization enabling it to run on systems with as little as 16GB memory.
ollama run gpt-oss:20b-cloud
The models are post-trained with MoE weights quantized to MXFP4 format (4.25 bits per parameter). The MoE weights cover 90+% of the total parameter count, so the 20B model runs on systems with as little as 16GB memory. Ollama supports MXFP4 natively without additional quantization.
:20b-cloud serves it on Ollama's infrastructure; the local tag runs on ~16GB systems.