Open models by OpenAI
Advanced open-weight reasoning models to customize for any use case and run anywhere.
Permissive license
Designed for agentic tasks
Deeply customizable
Full chain-of-thought
Interactive demo
We built a simple playground where developers can try both models in the browser.
Model performance
gpt-oss-120b | gpt-oss-20b | OpenAI o3 | OpenAI o4-mini | |
Reasoning & knowledge | ||||
MMLU | 90.0 | 85.3 | 93.4 | 93.0 |
GPQA Diamond | 80.1 | 71.5 | 83.3 | 81.4 |
Humanity’s Last Exam | 19.0 | 17.3 | 24.9 | 17.7 |
Competition math | ||||
AIME 2024 | 96.6 | 96.0 | 95.2 | 98.7 |
AIME 2025 | 97.9 | 98.7 | 98.4 | 99.5 |
Advancing safety standards for open models
Safety is foundational to our open models
Comprehensive safety testing
Our partners
We’re working with leading deployment and hardware companies to offer these models to the open-source community.
Resources
We want to hear from you
Share feedback and feature requests that may guide future open models. Please note: you won’t receive a direct response. For support and discussion, visit our Hugging Face Community.