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Try GPT 5.1 in the Workbench

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Model ID: gpt-5-1-2025-11-13 GPT 5.1 is an LLM that excels in adaptive reasoning and reliably following instructions, dynamically allocating computational effort based on task complexity. It automatically routes requests to either a fast, conversational model (Instant) or a more analytical, deeper reasoning model (Thinking), depending on the nature of the prompt, which improves both speed and response quality for a wide range of tasks. Some other noteworthy features of GPT 5.1 include expanded controls for personalizing tone and style, as well as improved performance in coding and math-related queries. *Quantization is specific to the inference provider and the model may be offered with different quantization levels by other providers.

Example request

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Request parameters

This model follows the standard OpenAI chat completions request body. See the chat completions reference for the full parameter list.