GPT-OSS 20B
A 21-billion-parameter open-weight model from OpenAI, designed for efficient reasoning and long-context usage (≈ 128K tokens).
Model Details
Provider
OpenAI
Model Type
text
Context Window
128,000 tokens
Pricing
Input (1M)$0.00
Output (1M)$0.00
Capabilities
- Open-weight / Apache 2.0 licensed: you can use, modify, and deploy freely (commercially & academically) under permissive terms.
- Large model size (≈ 21B parameters) with Mixture-of-Experts (MoE) architecture: only ~3.6B parameters active per token, yielding efficient inference.
- Very long context window support: up to ~128 K tokens (or ~131 K tokens per some sources) enabling in-depth reasoning, long documents, or multi-turn context.
- Adjustable reasoning effort: you can trade latency vs quality by tuning “reasoning effort” levels.
- Efficient hardware requirements (for its class): designed to run on a single 16 GB-class GPU or optimized local deployments for lower latency applications.
- Strong for tasks such as reasoning, tool-use, structured output, chain-of-thought debugging: because the model is open and you can inspect its chain of thought.
- Flexibility: since weights are available, you can self-host, fine-tune, or deploy offline, giving more control than closed API models.