gpt-oss-20b
Open Weights
OpenAI
The smaller of OpenAI's two open-weight models (August 2025, Apache 2.0), a 21B-parameter mixture-of-experts model with 3.6B active parameters that delivers results similar to o3-mini and runs on edge devices with just 16GB of memory.
Strengths
- Open weights under permissive Apache 2.0
- Similar results to o3-mini on common benchmarks
- 21B-parameter MoE with only 3.6B active parameters
- Runs on edge devices with just 16GB of memory
- 128K context with tool use and reasoning
Caveats
- Text-only (no vision or audio input)
- Smaller capacity trails gpt-oss-120b and proprietary frontier models
- Output-length limits embedded by OpenAI policy
- Vendor
- OpenAI
- Context Window
- 131,072 tokens
- License
- Apache-2.0
- Release Date
- 2025-08-05
- Modalities
- text
Capabilities
Vision
Audio
Video
Tool Use
Pricing
Open weights under Apache 2.0 - free to download and self-host; runs within 16GB of memory (laptops/edge). Hosted API providers vary.