gpt-oss-120b
OpenAI · 2025-08-05 · 116.8B parameters
gpt-oss-120b is the larger of OpenAI's two Apache 2.0-licensed gpt-oss reasoning models, which are the company's first open-weight language models since GPT-2. Its checkpoint contains exactly 116,829,156,672 logical parameters after unpacking MXFP4 weights and excluding quantization scales; OpenAI reports approximately 5.1B active parameters per token. It is a text-only mixture-of-experts model with configurable reasoning effort and training for tool use.