GPT-OSS 20B

About this model

GPT-OSS 20B is a compact 21B parameter Mixture-of-Experts model with 3.6B active parameters, designed for lower latency and local deployment. Runs within 16GB memory with configurable reasoning effort, full chain-of-thought access, and native agentic capabilities including function calling and structured outputs. Released under Apache 2.0 license, ideal for specialized fine-tuning on consumer hardware. Companion model to GPT-OSS 120B optimized for speed while maintaining strong reasoning capabilities.

Technical specifications

Capabilities

Input modalities

Output modalities

Reasoning

Default on high

Knowledge horizon