OpenAI
gpt-oss-20b is a 21-billion parameter open-weight model released by OpenAI under the Apache 2.0 license. Its core feature is a Mixture-of-Experts (MoE) architecture that uses only 3.6B active parameters, enabling low-latency inference and deployment on consumer GPUs. The model also supports fine-tuning, function calling, tool use, and structured outputs.
gpt-oss-20b is a 21-billion parameter open-weight model released by OpenAI under the Apache 2.0 license. Its core feature is a Mixture-of-Experts (MoE) architecture that uses only 3.6B active parameters, enabling low-latency inference and deployment on consumer GPUs. The model also supports fine-tuning, function calling, tool use, and structured outputs.
gpt-oss-20b has a 128,000 token context window.
On AIHubMix, gpt-oss-20b costs $0.11 per million input tokens and $0.55 per million output tokens.
gpt-oss-20b accepts text input.
gpt-oss-20b supports thinking, function calling and structured outputs. Per-protocol parameter support is listed in the capability table on this page.
gpt-oss-20b is available through the AIHubMix unified API. The API is OpenAI-compatible: point your OpenAI SDK at https://aihubmix.com/v1, use your AIHubMix API key, and set the model name to gpt-oss-20b — no other code changes needed.
gpt-oss-20b is developed by OpenAI. AIHubMix aggregates it alongside models from other providers behind one API and one bill.
gpt-oss-20b was released on August 5, 2025 by OpenAI.
Free version: GPT Oss 20B (free)
GPT-6.1 Sol is OpenAI's latest model in the GPT-6 series, specifically designed for…
GPT-6 Luna is OpenAI's latest and most efficient model, designed for focused…
GPT-6 Sol is OpenAI's latest model in the GPT-6 series, specifically designed for complex…
GPT-6 Astra is OpenAI's newest and most intelligent model, with industry-leading…
OpenAI's latest realtime speech-to-text model, built for low-latency use — it streams…
GPT-Realtime-2.1 is a reasoning speech-to-speech model for the Realtime API, with tool…
Use gpt-oss-20b via the AIHubMix unified API — one interface for every major LLM.