gpt-oss-120b is an open-weight, 117B-parameter Mixture-of-Experts (MoE) model from OpenAI, built for advanced reasoning, agentic behavior, and versatile production use cases. It activates 5.1B parameters per forward pass and is optimized to run efficiently on a single H100 GPU with native MXFP4 quantization. The model supports configurable reasoning depth, full chain-of-thought access, and native tool capabilities such as function calling, web browsing, and structured output generation.
| Creator | OpenAI |
| Release Date | August, 2025 |
| License | Apache 2.0 |
| Context Window | 131,000 |
| Image Input Support | No |
| Open Source (Weights) | Yes |
| Parameters | 117B, 5.1B active at inference time |
| Model Weights | Click here |
