OpenAI

GPT-5.1

Generally availableProprietary400K contextReasoning

Summary

GPT-5.1 is a proprietary language model from OpenAI, released on 13 Nov 2025. It accepts text and images and generates text, with a 400K-token context window and up to 128K output tokens per response. As of 4 Oct 2026, the lowest listed API price is $1.25 per million input tokens and $10 per million output tokens (OpenAI API), across 5 providers we track.

Sharper GPT-5 generation for coding, product work, and tool-assisted tasks

Last verified 4 Oct 2026. Every figure on this page links to its source.

Specifications

DeveloperOpenAI
Release date13 Nov 2025 [models.dev]
StatusGenerally available [models.dev]
WeightsProprietary (API only) [models.dev]
Context window400K (400,000 tokens) [models.dev]
Max output128K tokens [models.dev]
Knowledge cutoff30 Sept 2024 [models.dev]
InputText and images [models.dev]
OutputText [models.dev]
Reasoning modeYes [models.dev]
Tool callingYes [models.dev]
Structured outputYes [models.dev]

GPT-5.1 API pricing by provider

USD per million tokens. Sorted by input price.

ProviderInputOutputCached inputContextSource
OpenAI API
gpt-5.1
$1.25$10$0.13400Kmodels.dev, 4 Oct 2026
Databricks
databricks-gpt-5-1
$1.25$10$0.13400Kmodels.dev, 4 Oct 2026
Azure AI Foundry
gpt-5.1
$1.25$10$0.13400Kmodels.dev, 4 Oct 2026
OpenRouter
openai/gpt-5.1
$1.25$10$0.13400KOpenRouter, 4 Oct 2026
Snowflake Cortex
openai-gpt-5.1
–––272Kmodels.dev, 4 Oct 2026

Frequently asked questions

What is the context window of GPT-5.1?

GPT-5.1 has a context window of 400,000 tokens (400K) and can generate up to 128,000 tokens in a single response, according to models.dev.

How much does the GPT-5.1 API cost?

Through OpenAI API, GPT-5.1 costs $1.25 per million input tokens and $10 per million output tokens. Prices last verified 4 Oct 2026.

Is GPT-5.1 open source?

No. GPT-5.1 is a proprietary model; OpenAI has not released its weights. It is available through APIs including OpenAI API, Databricks, Azure AI Foundry, OpenRouter.

When was GPT-5.1 released?

OpenAI released GPT-5.1 on 13 Nov 2025, according to models.dev.

Which providers offer GPT-5.1?

We track GPT-5.1 on 5 providers: OpenAI API, Databricks, Azure AI Foundry, OpenRouter, Snowflake Cortex.

Change history

No changes detected since we started tracking this model. We re-check every source daily.

Sources