OpenAI: GPT-5.1 Chat

openai/gpt-5.1-chat

Created Nov 13, 2025128,000 context

$1.25/M input tokens$10/M output tokens$10/K web search

GPT-5.1 Chat (AKA Instant is the fast, lightweight member of the 5.1 family, optimized for low-latency chat while retaining strong general intelligence. It uses adaptive reasoning to selectively “think” on harder queries, improving accuracy on math, coding, and multi-step tasks without slowing down typical conversations. The model is warmer and more conversational by default, with better instruction following and more stable short-form reasoning. GPT-5.1 Chat is designed for high-throughput, interactive workloads where responsiveness and consistency matter more than deep deliberation.

OpenAI: GPT-5.1 Chat

openai/gpt-5.1-chat

Created Nov 13, 2025128,000 context

$1.25/M input tokens$10/M output tokens$10/K web search

GPT-5.1 Chat (AKA Instant is the fast, lightweight member of the 5.1 family, optimized for low-latency chat while retaining strong general intelligence. It uses adaptive reasoning to selectively “think” on harder queries, improving accuracy on math, coding, and multi-step tasks without slowing down typical conversations. The model is warmer and more conversational by default, with better instruction following and more stable short-form reasoning. GPT-5.1 Chat is designed for high-throughput, interactive workloads where responsiveness and consistency matter more than deep deliberation.

Sample code and API for GPT-5.1 Chat

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Using third-party SDKs

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