How much does GPT-5.1 cost?

GPT-5.1 costs $1.25/M input tokens and $10.00/M output tokens, with separate rates for Cache Read at $0.13/M tokens.

What is the context length of GPT-5.1?

GPT-5.1 has a 400,000 token context window. It supports up to 128,000 completion tokens.

Does GPT-5.1 support tool calling and structured outputs?

Yes. GPT-5.1 accepts tools and tool_choice for function calling. It also supports structured outputs via a JSON schema in response_format.

What inputs and outputs does GPT-5.1 support?

GPT-5.1 accepts images, text, and files such as PDFs as input and returns text.

Which providers serve GPT-5.1?

GPT-5.1 is served by 2 providers on OpenRouter: OpenAI and Azure. Requests are routed to the best available provider, with automatic failover to the others, and you can pin or exclude providers with provider routing.

When was GPT-5.1 released?

GPT-5.1 was released on November 13, 2025.

OpenAI: GPT-5.1

openai/gpt-5.1

Compare

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

Modalities

In / out price

$1.25 / $10per 1M

Context

400K

Released

Nov 13, 2025

Providers

Different companies host the same model. OpenRouter routes your request to one of them based on the routing mode you pick: Balanced (price + speed), Nitro (fastest), or Floor (cheapest).

Latency / throughput


	$1.25	$10.00	$0.13	3.35s	66 tok/s	100.00%
	$1.25	$10.00	$0.125	1.35s	54 tok/s	100.00%
Not used in Standard routing:Why these endpoints are not used
Flex	$0.625	$5.00	$0.0625	0.71s	145 tok/s	100.00%
	$1.375	$11.00	$0.143	2.29s	106 tok/s	100.00%
Fast	$2.50	$20.00	$0.25	--	--	100.00%

Input $1.25Output $10.00
66 tok/s100.00% uptime
Input $1.25Output $10.00
54 tok/s100.00% uptime
Not used in Standard routing:Why these endpoints are not used
Input $0.625Output $5.00
Flex
145 tok/s100.00% uptime
Input $1.375Output $11.00
106 tok/s100.00% uptime
Input $2.50Output $20.00
Fast
-- tok/s100.00% uptime

Pricing

The average price customers actually pay for this model, next to the prices providers post. Caching and discounts mean the price actually paid is often well below the listed one.

Weighted average

Input

$0.3904/M tokens

Output

$9.481/M tokens

GPT-5.1 — Price history

Price history

No effective price data for this selection

		$0.386	$10.00	76.8%	96.4%
		$0.717	$10.00	47.5%	1.7%
Not used in Standard routing:Why these endpoints are not used
	Flex	$0.308	$5.00	56.3%	1.8%
	Fast	$0.335	$20.00	96.2%	0.1%
		$0.778	$11.00	48.4%	0.1%

Effective in $0.386Effective out $10.00
Token share
96.4%
Effective in $0.717Effective out $10.00
Token share
1.7%
Not used in Standard routing:Why these endpoints are not used
Effective in $0.308Effective out $5.00
FlexToken share
1.8%
Effective in $0.335Effective out $20.00
FastToken share
0.1%
Effective in $0.778Effective out $11.00
Token share
0.1%

Uptime

Uptime is the percentage of the past 3 days that at least one provider was responding to requests. Availability is the percentage of time that inference was successfully served. OpenRouter continuously monitors and uses the next-best provider when one returns an error.

Uptime (3d)

100.00%

Availability (3d)

99.94%

Availability over the last 3 days

Last 72 hours

Availability 99.94%

3 Days Ago2 Days AgoYesterdayNow

Availability over the last 24 hours

OpenRouter Availability

99.96%

Without Routing

98.35%

When an error occurs in an upstream provider, we can recover by routing to another healthy provider, if your request filters allow it. You can access per-provider uptime data programmatically through the Endpoints API. Learn more about our load balancing and provider routing options.

Benchmarks

Scores on standardized evaluations and this model’s own outputs on shared benchmark prompts. Higher percentages are better — and each rank shows where this model lands among the models evaluated on that source.

Benchmark score summary for OpenAI: GPT-5.1 (Artificial Analysis, Design Arena and Vals AI)
Source	Benchmark	Score
Artificial Analysis	GPT-5.1 (Non-reasoning) GPQA Diamond	64.3%
Artificial Analysis	GPT-5.1 (Non-reasoning) HLE	5.3%
Artificial Analysis	GPT-5.1 (Non-reasoning) IFBench	43.2%
Artificial Analysis	GPT-5.1 (Non-reasoning) τ²-Bench Telecom	46.5%
Artificial Analysis	GPT-5.1 (Non-reasoning) AA-LCR	45.0%
Artificial Analysis	GPT-5.1 (Non-reasoning) CritPt	0.0%
Artificial Analysis	GPT-5.1 (Non-reasoning) LiveCodeBench	49.4%
Artificial Analysis	GPT-5.1 (Non-reasoning) Terminal-Bench Hard	22.7%
Artificial Analysis	GPT-5.1 (Non-reasoning) MMLU-Pro	80.1%
Artificial Analysis	GPT-5.1 (Non-reasoning) AIME 2025	38.0%
Artificial Analysis	GPT-5.1 (High) Coding Index	49.4
Artificial Analysis	GPT-5.1 (High) GPQA Diamond	87.3%
Artificial Analysis	GPT-5.1 (High) HLE	28.5%
Artificial Analysis	GPT-5.1 (High) IFBench	72.9%
Artificial Analysis	GPT-5.1 (High) τ²-Bench Telecom	81.9%
Artificial Analysis	GPT-5.1 (High) AA-LCR	80.0%
Artificial Analysis	GPT-5.1 (High) τ-Bench Banking	15.9%
Artificial Analysis	GPT-5.1 (High) GDPval-AA	16.7%
Artificial Analysis	GPT-5.1 (High) CritPt	4.9%
Artificial Analysis	GPT-5.1 (High) LiveCodeBench	86.8%
Artificial Analysis	GPT-5.1 (High) Terminal-Bench Hard	45.5%
Artificial Analysis	GPT-5.1 (High) Terminal-Bench 2.1	52.4%
Artificial Analysis	GPT-5.1 (High) MMLU-Pro	87.0%
Artificial Analysis	GPT-5.1 (High) AIME 2025	94.0%
Design Arena	GPT-5.1 (High) Models Arena 3D Elo	1039
Design Arena	GPT-5.1 (High) Models Arena Asciiart Elo	1056
Design Arena	GPT-5.1 (High) Models Arena Code Categories Elo	1160
Design Arena	GPT-5.1 (High) Models Arena Data Visualization Elo	1193
Design Arena	GPT-5.1 (High) Models Arena Game Development Elo	1168
Design Arena	GPT-5.1 (High) Models Arena SVG Elo	1140
Design Arena	GPT-5.1 (High) Models Arena UI Component Elo	1149
Design Arena	GPT-5.1 (High) Models Arena Website Elo	1178
Vals AI	GPT 5.1 AIME	93.3%
Vals AI	GPT 5.1 CaseLaw v2	73.4%
Vals AI	GPT 5.1 CorpFin v2	63.8%
Vals AI	GPT 5.1 Finance Agent v1.1	55.3%
Vals AI	GPT 5.1 GPQA Diamond	86.6%
Vals AI	GPT 5.1 IOI v1	21.5%
Vals AI	GPT 5.1 LiveCodeBench	86.5%
Vals AI	GPT 5.1 LegalBench	85.7%
Vals AI	GPT 5.1 MedCode	52.7%
Vals AI	GPT 5.1 MedQA	96.4%
Vals AI	GPT 5.1 MedScribe	88.1%
Vals AI	GPT 5.1 MGSM	93.0%
Vals AI	GPT 5.1 MMLU Pro	86.4%
Vals AI	GPT 5.1 MMMU Pro	83.2%
Vals AI	GPT 5.1 MortgageTax	61.4%
Vals AI	GPT 5.1 SAGE v1	43.2%
Vals AI	GPT 5.1 SWE-bench	69.8%
Vals AI	GPT 5.1 TaxEval v2	74.9%
Vals AI	GPT 5.1 Terminal-Bench 2.0	44.9%
Vals AI	GPT 5.1 Vals Index	53.6%
Vals AI	GPT 5.1 Vals Multimodal Index	52.7%
Vals AI	GPT 5.1 Vibe Code Bench v1.1	24.6%

Apps

Public apps that send the most traffic to this model. Good signal for what real production workloads look like — and a hint at which use cases this model is best suited for.

Spicy Writer

new

2.96Btokens

Candace

new

1.33Btokens

Dify.AI

Effortlessly manage autonomous agents and workflows.

958Mtokens

AchieveApex

new

869Mtokens

Hermes Agent

Hermes Agent is an open-source, self-improving AI agent by Nous Research that runs persistently with memory across sessions, and builds reusable skills from experience. It comes with 40+ built-in tools, including web search, browser automation, and vision, plus scheduled automations and subagents.

864Mtokens

Rest of OpenRouter

6.16B

Top 5 Apps

157M

Available through EU in-region routing

OpenAI: GPT-5.1 is available through EU in-region routing. Requests sent to eu.openrouter.ai are decrypted in the EU and routed only to shared provider endpoints in Europe (the EU/EEA, the UK, and Switzerland).

Providers in Europe

Azure

Prices in Europe

Azure: $1.375/M tokens input, $11/M tokens output

Base URL

https://eu.openrouter.ai/api/v1

Plan

Requires Business or Enterprise. Self-serve on Business: no contract, no monthly minimum. OpenRouter Business for EU in-region routing

Fails closed: if no shared provider endpoint in Europe is available, the request errors instead of leaving the region. Requests served by your own BYOK key go to your deployment’s region, which you control. In-region routing docs

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OpenAI: GPT-5.1

Providers