free open weights Engineers
GPT-OSS
by OpenAI
OpenAI's open-weight model family, its first downloadable models since GPT-2.
4/5
Visit GPT-OSS - Context window
- 128K tokens
- Parameters
- 20B and 120B
- Open weights
- Yes
- Released
- Aug 2025
Pros
- + Open weights from OpenAI under a permissive license
- + 20B variant runs on a single high-end GPU
- + Strong reasoning for its size
Cons
- − Below OpenAI's closed flagship models
- − 120B variant still needs capable hardware
- − Text-only, no native multimodality
What Is GPT-OSS
GPT-OSS is OpenAI’s open-weight model family — its first downloadable models since GPT-2, released under a permissive license in 20B and 120B parameter sizes.
In Practice
GPT-OSS lets teams run an OpenAI-designed model fully on their own infrastructure for privacy, cost, or offline use. The 20B variant is small enough for a single high-end GPU, making it a practical option for local and self-hosted deployments.