Compare gpt-oss-20b from OpenAI and GPT Oss 20B (free) from OpenAI on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
gpt-oss-20bGPT Oss 20B (free)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.
Developed by OpenAI, gpt-oss-20b-free is an open-weight 21B parameter model released under the Apache 2.0 license. This model utilizes a Mixture-of-Experts (MoE) architecture with 3.6B active parameters per forward pass. It supports an expansive context window of up to 131,072 tokens, making it well-suited for long-context tasks.
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gpt-oss-20b accepts 128,000 and GPT Oss 20B (free) accepts 131,072 input tokens.
gpt-oss-20b accepts text input and supports thinking, function calling and structured outputs; GPT Oss 20B (free) accepts text input and supports reasoning, tool calling and long context.
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