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Model detail

gpt-5.1-2025-11-13

Provided by OpenAI
Pay-as-you-go

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 to allocate computation dynamically, responding quickly to simple queries while spending more depth on complex tasks. The model produces clearer, more grounded explanations with reduced jargon, making it easier to follow even on technical or multi-step problems. Built for broad task coverage, GPT-5.1 delivers consistent gains across math, coding, and structured analysis workloads, with more coherent long-form answers and improved tool-use reliability. It also features refined conversational alignment, enabling warmer, more intuitive responses without compromising precision. GPT-5.1 serves as the primary full-capability successor to GPT-5

Model specs

Context length
400K
Max output
128K
I/O modalities
Text / Image
Released
2025-11

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API endpoints

One MixRoute gateway, OpenAI-compatible

  • OpenAI-compatible /v1/chat/completions POST

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Pricing

Flat rate, unit: /1M Tokens

Input

$1.2500 /1M Tokens

Completion

$10.0000 /1M Tokens

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Selection summary

Quickly judge whether it fits your workload

What is this model good for?

General-purpose reasoning with adaptive computation

Use gpt-5.1-2025-11-13 for math, coding, and structured analysis. It delivers improved instruction adherence and more natural conversational style with adaptive reasoning.

What should you check before using it?

Confirm the snapshot date matches your stability needs

This is the 2025-11-13 snapshot of GPT-5.1. Verify that this version provides the stability you need for your workloads.

Why use it through MixRoute?

Use the OpenAI-compatible endpoint with stable model ID

Use the confirmed compatible endpoint with model ID gpt-5.1-2025-11-13 through MixRoute for a pinned version.

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Token cost estimator

Live estimate from this page's pricing, not an actual bill

This model has no cache-read price; caching is not counted

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FAQ

gpt-5.1 is intended for general reasoning, coding, structured analysis, and conversational tasks that benefit from strong instruction adherence and adaptive reasoning.

One endpoint, a testable decision

Test this model and alternate routes with the same request format

Start from a real workload, then let quality, total cost, and failure conditions decide whether to send production traffic.