GPT-5.1 is an AI model from OpenAI in the GPT series. Agent Mag tracks its context window, pricing, modalities, and supported API parameters on this page.

How do you use GPT-5.1?

GPT-5.1 can be called through OpenRouter's OpenAI-compatible API using the model ID openai/gpt-5.1. This page includes a ready-to-run curl example and the supported parameter list.

GPT-5.1 is a paid model in the OpenRouter catalog, with separate input and output token pricing shown on this page.

GPT-5.1

All models

OpenAIGPT

GPT-5.1

400K context

$1.25/M input

$10.00/M output

GPT-5.1 is an AI model from OpenAI built for agent workflows, with support for image, text, file input and text output. GPT-5.1 is the latest frontier-grade model in the GPT-5 series, offering stronger general-purpose reasoning, improved instruction adherence, and a more natural conversational style compared to GPT-5. It uses adaptive reasoning...

What is GPT-5.1?

GPT-5.1 is an AI model from OpenAI that Agent Mag tracks for pricing, context window, modalities, benchmarks, and API compatibility. Builders can use this page to compare GPT-5.1 against other models for agent workflows and production deployments.

Model ID

GPT-5.1 is the latest frontier-grade model in the GPT-5 series, offering stronger general-purpose reasoning, improved instruction adherence, and a more natural conversational style compared to GPT-5. It uses adaptive reasoning...

Modalities

Input

imagetextfile

Output

text

Supported Parameters

include_reasoningmax_completion_tokensmax_tokensreasoningresponse_formatseedstructured_outputstool_choicetools

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