Where is the GPT-5.5 documentation?

The GPT-5.5 documentation on OpenRouter includes the GPT-5.4 Migration Guide cookbook and the GPT-5.5 Price Increase: What It Actually Costs blog post. The quickstart covers API keys and your first request, and the API reference lists every parameter.

How much does GPT-5.5 cost?

GPT-5.5 costs $5.00/M input tokens and $30.00/M output tokens, with separate rates for Cache Read at $0.50/M tokens and Web Search at $10.00/1K calls.

What is the context length of GPT-5.5?

GPT-5.5 has a 1,050,000 token context window. It supports up to 128,000 completion tokens.

Does GPT-5.5 support tool calling and structured outputs?

Yes. GPT-5.5 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-5.5 support?

GPT-5.5 accepts files such as PDFs, images, and text as input and returns text.

Which providers serve GPT-5.5?

GPT-5.5 is served by 3 providers on OpenRouter: OpenAI, Azure, and Amazon Bedrock. 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-5.5 released?

GPT-5.5 was released on April 24, 2026. Its knowledge cutoff is December 1, 2025.

OpenAI: GPT-5.5

openai/gpt-5.5

Compare

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token context window (922K input, 128K output) with support for text and image inputs, enabling large-scale reasoning, coding, and multimodal workflows within a single system.

Modalities

In / out price

$5 / $30per 1M

Context

1.1M

Released

Apr 24, 2026

Knowledge cutoff

Dec 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


	$5.00	$30.00	$0.50	1.28s	55 tok/s	100.00%
	$5.00	$30.00	$0.50	11.04s	39 tok/s	100.00%
Not used in Standard routing:Why these endpoints are not used
Flex	$2.50	$15.00	$0.25	7.08s	118 tok/s	100.00%
	$5.50	$33.00	$0.55	1.54s	62 tok/s	100.00%
	$5.50	$33.00	$0.55	0.75s	71 tok/s	100.00%
	$5.50	$33.00	$0.55	0.88s	45 tok/s	--
Fast	$12.50	$75.00	$1.25	3.10s	105 tok/s	100.00%

Input $5.00Output $30.00
55 tok/s100.00% uptime
Input $5.00Output $30.00
39 tok/s100.00% uptime
Not used in Standard routing:Why these endpoints are not used
Input $2.50Output $15.00
Flex
118 tok/s100.00% uptime
Input $5.50Output $33.00
62 tok/s100.00% uptime
Input $5.50Output $33.00
71 tok/s100.00% uptime
Input $5.50Output $33.00
45 tok/s-- uptime
Input $12.50Output $75.00
Fast
105 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

$2.046/M tokens

Output

$30.13/M tokens

GPT-5.5 — Price history

Price history

No effective price data for this selection

		$1.755	$30.00	72.1%	10.3%
		$2.056	$30.02	66.9%	88.9%
Not used in Standard routing:Why these endpoints are not used
	Flex	$0.989	$15.00	67.2%	0.2%
		$1.621	$33.00	78.4%	0.1%
		$2.214	$33.00	66.4%	0.1%
		$2.502	$33.00	60.6%	0.0%
	Fast	$9.602	$75.00	25.8%	0.3%

Effective in $1.755Effective out $30.00
Token share
10.3%
Effective in $2.056Effective out $30.02
Token share
88.9%
Not used in Standard routing:Why these endpoints are not used
Effective in $0.989Effective out $15.00
FlexToken share
0.2%
Effective in $1.621Effective out $33.00
Token share
0.1%
Effective in $2.214Effective out $33.00
Token share
0.1%
Effective in $2.502Effective out $33.00
Token share
0.0%
Effective in $9.602Effective out $75.00
FastToken share
0.3%

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)

99.90%

Availability over the last 3 days

Last 72 hours

Availability 99.90%

3 Days Ago2 Days AgoYesterdayNow

Availability over the last 24 hours

OpenRouter Availability

99.89%

Without Routing

99.51%

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-5.5 (Artificial Analysis, Design Arena and Vals AI)
Source	Benchmark	Score
Artificial Analysis	GPT-5.5 (Xhigh) Coding Index	74.9
Artificial Analysis	GPT-5.5 (Xhigh) Agentic Index	36.4
Artificial Analysis	GPT-5.5 (Xhigh) GPQA Diamond	93.5%
Artificial Analysis	GPT-5.5 (Xhigh) HLE	45.8%
Artificial Analysis	GPT-5.5 (Xhigh) IFBench	75.9%
Artificial Analysis	GPT-5.5 (Xhigh) τ²-Bench Telecom	93.9%
Artificial Analysis	GPT-5.5 (Xhigh) AA-LCR	84.3%
Artificial Analysis	GPT-5.5 (Xhigh) τ-Bench Banking	39.0%
Artificial Analysis	GPT-5.5 (Xhigh) GDPval-AA	42.9%
Artificial Analysis	GPT-5.5 (Xhigh) CritPt	27.1%
Artificial Analysis	GPT-5.5 (Xhigh) SciCode	55.8%
Artificial Analysis	GPT-5.5 (Xhigh) Terminal-Bench Hard	60.6%
Artificial Analysis	GPT-5.5 (Xhigh) Terminal-Bench 4.0	14.6%
Artificial Analysis	GPT-5.5 (Xhigh) Terminal-Bench 2.1	84.3%
Artificial Analysis	GPT-5.5 (Low) Coding Index	60.9
Artificial Analysis	GPT-5.5 (Low) GPQA Diamond	91.0%
Artificial Analysis	GPT-5.5 (Low) HLE	32.7%
Artificial Analysis	GPT-5.5 (Low) IFBench	64.4%
Artificial Analysis	GPT-5.5 (Low) τ²-Bench Telecom	83.9%
Artificial Analysis	GPT-5.5 (Low) AA-LCR	81.0%
Artificial Analysis	GPT-5.5 (Low) τ-Bench Banking	24.9%
Artificial Analysis	GPT-5.5 (Low) GDPval-AA	27.7%
Artificial Analysis	GPT-5.5 (Low) CritPt	8.0%
Artificial Analysis	GPT-5.5 (Low) Terminal-Bench Hard	52.3%
Artificial Analysis	GPT-5.5 (Low) Terminal-Bench 2.1	65.5%
Artificial Analysis	GPT-5.5 (Non-reasoning) Coding Index	56.5
Artificial Analysis	GPT-5.5 (Non-reasoning) GPQA Diamond	76.8%
Artificial Analysis	GPT-5.5 (Non-reasoning) HLE	13.7%
Artificial Analysis	GPT-5.5 (Non-reasoning) IFBench	46.1%
Artificial Analysis	GPT-5.5 (Non-reasoning) τ²-Bench Telecom	69.3%
Artificial Analysis	GPT-5.5 (Non-reasoning) AA-LCR	64.0%
Artificial Analysis	GPT-5.5 (Non-reasoning) τ-Bench Banking	14.8%
Artificial Analysis	GPT-5.5 (Non-reasoning) GDPval-AA	23.9%
Artificial Analysis	GPT-5.5 (Non-reasoning) CritPt	1.4%
Artificial Analysis	GPT-5.5 (Non-reasoning) Terminal-Bench Hard	49.2%
Artificial Analysis	GPT-5.5 (Non-reasoning) Terminal-Bench 2.1	61.0%
Artificial Analysis	GPT-5.5 (High) Coding Index	71.6
Artificial Analysis	GPT-5.5 (High) Agentic Index	34.3
Artificial Analysis	GPT-5.5 (High) GPQA Diamond	93.2%
Artificial Analysis	GPT-5.5 (High) HLE	45.0%
Artificial Analysis	GPT-5.5 (High) IFBench	71.6%
Artificial Analysis	GPT-5.5 (High) τ²-Bench Telecom	93.0%
Artificial Analysis	GPT-5.5 (High) AA-LCR	84.3%
Artificial Analysis	GPT-5.5 (High) τ-Bench Banking	36.7%
Artificial Analysis	GPT-5.5 (High) GDPval-AA	41.8%
Artificial Analysis	GPT-5.5 (High) CritPt	25.4%
Artificial Analysis	GPT-5.5 (High) SciCode	56.1%
Artificial Analysis	GPT-5.5 (High) Terminal-Bench Hard	59.8%
Artificial Analysis	GPT-5.5 (High) Terminal-Bench 4.0	9.1%
Artificial Analysis	GPT-5.5 (High) Terminal-Bench 2.1	79.4%
Artificial Analysis	GPT-5.5 (Medium) Coding Index	71.5
Artificial Analysis	GPT-5.5 (Medium) Agentic Index	29.5
Artificial Analysis	GPT-5.5 (Medium) GPQA Diamond	92.6%
Artificial Analysis	GPT-5.5 (Medium) HLE	42.4%
Artificial Analysis	GPT-5.5 (Medium) IFBench	71.0%
Artificial Analysis	GPT-5.5 (Medium) τ²-Bench Telecom	91.8%
Artificial Analysis	GPT-5.5 (Medium) AA-LCR	83.0%
Artificial Analysis	GPT-5.5 (Medium) τ-Bench Banking	29.9%
Artificial Analysis	GPT-5.5 (Medium) GDPval-AA	37.1%
Artificial Analysis	GPT-5.5 (Medium) CritPt	18.6%
Artificial Analysis	GPT-5.5 (Medium) SciCode	54.5%
Artificial Analysis	GPT-5.5 (Medium) Terminal-Bench Hard	57.6%
Artificial Analysis	GPT-5.5 (Medium) Terminal-Bench 4.0	5.1%
Artificial Analysis	GPT-5.5 (Medium) Terminal-Bench 2.1	80.5%
Design Arena	GPT-5.5 Agents Arena Agenticgamedev Elo	1122
Design Arena	GPT-5.5 Agents Arena Agentichtmlslides Elo	1084
Design Arena	GPT-5.5 Agents Arena Agenticslides Elo	1150
Design Arena	GPT-5.5 Agents Arena Agenticslides(Html) Elo	1077
Design Arena	GPT-5.5 Agents Arena Agenticslides(Python-Pptx) Elo	1155
Design Arena	GPT-5.5 Agents Arena Androidnative Elo	1154
Design Arena	GPT-5.5 Agents Arena Full Stack Elo	1061
Design Arena	GPT-5.5 Agents Arena Godotgamedev Elo	1152
Design Arena	GPT-5.5 Agents Arena Htmlslides Elo	962
Design Arena	GPT-5.5 Agents Arena Mobile Apps Elo	1134
Design Arena	GPT-5.5 Agents Arena Pptxslides Elo	1157
Design Arena	GPT-5.5 Agents Arena Python-Pptxslides Elo	1152
Design Arena	GPT-5.5 Agents Arena Python-Pptxslides Elo	1077
Design Arena	GPT-5.5 Agents Arena Webapps Elo	1093
Design Arena	GPT-5.5 Models Arena 3D Elo	1175
Design Arena	GPT-5.5 Models Arena Asciiart Elo	1247
Design Arena	GPT-5.5 Models Arena Code Categories Elo	1249
Design Arena	GPT-5.5 Models Arena Data Visualization Elo	1259
Design Arena	GPT-5.5 Models Arena Game Development Elo	1282
Design Arena	GPT-5.5 Models Arena SVG Elo	1225
Design Arena	GPT-5.5 Models Arena UI Component Elo	1250
Design Arena	GPT-5.5 Models Arena Website Elo	1248
Vals AI	GPT 5.5 CaseLaw v2	66.2%
Vals AI	GPT 5.5 Code Migration	45.2%
Vals AI	GPT 5.5 CorpFin v2	68.4%
Vals AI	GPT 5.5 EMB	64.5%
Vals AI	GPT 5.5 Finance Agent (v2)	51.8%
Vals AI	GPT 5.5 GPQA Diamond	93.2%
Vals AI	GPT 5.5 Harvey's Legal Agent Benchmark v1	3.8%
Vals AI	GPT 5.5 LiveCodeBench	85.3%
Vals AI	GPT 5.5 LegalBench	86.5%
Vals AI	GPT 5.5 Legal Research Bench	40.4%
Vals AI	GPT 5.5 MedCode	49.1%
Vals AI	GPT 5.5 MedScribe	86.9%
Vals AI	GPT 5.5 MMLU Pro	88.1%
Vals AI	GPT 5.5 MMMU Pro	88.3%
Vals AI	GPT 5.5 MortgageTax	68.8%
Vals AI	GPT 5.5 ProgramBench	0.5%
Vals AI	GPT 5.5 ProofBench v1	50.0%
Vals AI	GPT 5.5 Public Benefits Bench v1.1	60.9%
Vals AI	GPT 5.5 Vals RSI Index	16.5%
Vals AI	GPT 5.5 SAGE v1	51.5%
Vals AI	GPT 5.5 SkillsBench	62.2%
Vals AI	GPT 5.5 SRE Bench	3.8%
Vals AI	GPT 5.5 SWE-bench	82.6%
Vals AI	GPT 5.5 Tax Agent Bench	21.8%
Vals AI	GPT 5.5 TaxEval v2	75.0%
Vals AI	GPT 5.5 Terminal-Bench 2.1	76.4%
Vals AI	GPT 5.5 Vals Index	57.4%
Vals AI	GPT 5.5 Vals Multimodal Index	68.1%
Vals AI	GPT 5.5 Vibe Code Bench v1.1	69.8%

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.

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.

13.9Btokens

Framer

Create a professional website with Framer’s no-code AI website builder. Design freely, manage CMS content, optimize SEO, collaborate, and publish fast.

9.69Btokens

Codex

A coding agent that helps you build and ship with AI

7.57Btokens

omp

new

6.09Btokens

There are many coding agents, but this one is yours.

3.08Btokens

Rest of OpenRouter

1.67B

Top 5 Apps

454M

OpenAI: GPT Sol versions

Available through EU in-region routing

OpenAI: GPT-5.5 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: $5.50/M tokens input, $33/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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GPT Image 2.6 Flare

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GPT-6.1 Terra (batch)

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GPT-6 Luna Decisions

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GPT Astra Latest

This model always redirects to the latest model in the GPT Astra family.

Text1.1M context

OpenAI: GPT-5.5

Providers