Is GPT-5.1 Chat available on FastMetal?

Not at the moment. GPT-5.6 Sol, from the same lab, is available on the FastMetal API today.

What is the context window of GPT-5.1 Chat?

128,000 tokens, shared between the prompt and the response.

openai/gpt-5-1-chat

Not Available

GPT-5.1 Chat

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.

11/13/2025

128,000 tokens

Specifications

Modalities

Input

file

image

text

Output

text

Supported Parameters

max_tokens

response_format

seed

structured_outputs

tool_choice

tools

Max Output Tokens

16,384

Frequently asked questions

Is GPT-5.1 Chat available on FastMetal?: Not at the moment. GPT-5.6 Sol, from the same lab, is available on the FastMetal API today.
What is the context window of GPT-5.1 Chat?: 128,000 tokens, shared between the prompt and the response.

Models you can use on FastMetal