Compare Claude Opus 4.8 from Anthropic 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.
Claude Opus 4.8
GPT Oss 20B (free)Claude Opus 4.8 is Anthropic’s newest and most powerful publicly available model. It is suitable for the most complex tasks. It is Anthropic’s strongest model for complex reasoning, long-horizon agent programming, and highly autonomous work.claude-opus-4-8 does not display thought content by default; you need to set the additional parameter "display": "summarized" to enable it
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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Claude Opus 4.8 accepts 1,000,000 and GPT Oss 20B (free) accepts 131,072 input tokens. Maximum output per request is 128,000 tokens on Claude Opus 4.8 and 131,072 tokens on GPT Oss 20B (free).
Claude Opus 4.8 accepts text, image and PDF input and supports thinking, tool calling, function calling and structured outputs; GPT Oss 20B (free) accepts text input and supports reasoning, tool calling and long context.
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