OpenAI: GPT-5.5 API

openai/gpt-5.5

GPT-5.5 API combines file, image, and text input with a 1.05M context. Its high-effort configuration leads the current LLM2014 logic benchmark, while its standard Instant row represents a very different speed and quality point. ^[1]

The xhigh run ranks #1 with a 77.46 median and 83.80 best score; GPT-5.5 API Instant ranks #30 but completes far faster. This page treats the reasoning modes separately so buyers can weigh quality against latency and token use. ^[1][2]

MODALITIES

Price$2.5 / $15 / 1MCONTEXT1.05M

import OpenAI from "openai";

const client = new OpenAI({
  apiKey: process.env.API_NEED_API_KEY,
  baseURL: "https://apineed.com/v1"
});

const result = await client.chat.completions.create({
  model: "gpt-5.5",
  messages: [
    { role: "user", content: "Why is the sky blue?" }
  ]
});

console.log(result.choices[0].message.content);

Playground

Test GPT-5.5 API with representative production prompts before using gpt-5.5 in a live workflow.

Providers

APINEED lists GPT-5.5 API with file, image, and text input, text output, and a 1.05M context window. APINEED routing and prepaid rates are identified separately. ^[1]

API Need50% off

Uptime

Total Context

1.05M

Max Output

128K

Input

$2.5/ 1M

Output

$15/ 1M

Cache Read

$0.25/ 1M

Cache Write

Route priced

Discount

APINEED halves GPT-5.5’s $5 input and $30 output official rates. Output-heavy reasoning remains the larger cost driver, especially when higher effort expands generated tokens. The table compares official GPT-5.5 API pricing with the APINEED prepaid rate.

Official

Provider baseline

Input $5/ 1MOutput $30/ 1M

Baseline

APINEED50% off

Prepaid credits

Input $2.5/ 1MOutput $15/ 1M

Availability

APINEED continuously monitors GPT-5.5 API access and keeps requests on healthy capacity.

System statusLast 90 days

APINEED GATEWAY99.68% uptime

GPT-5.5 API Benchmarks

GPT-5.5’s xhigh row is #1, one place ahead of Kimi K3. Its Instant row is #30 with a 25-second measured time, demonstrating the family’s wide quality-speed envelope. The complete LLM2014 logic 2026-07 table remains below, with GPT-5.5 API highlighted when a current row exists. ^[2]


1st	GPT-5.5 (xhigh)	83.80	77.46	7.57%	494s	30,811	$25.51	$29.57
2nd	Kimi-K3 (max)	82.91	74.80	9.78%	1095s	39,912	$16.76	$15.00
3rd	Claude Opus 4.8 (xhigh)	82.62	66.70	19.27%	791s	41,833	$28.86	$24.64
4th	GPT-5.6 Sol (xhigh)	81.94	72.99	10.92%	369s	17,433	$14.43	$29.57
5th	Claude Opus 5 (xhigh)	78.38	71.88	8.29%	426s	26,392	$18.21	$24.64
6th	Qwen3.7-Max (xhigh)	74.56	66.95	10.21%	374s	54,207	$7.81	$5.14
7th	GLM-5.2 (max)	73.68	58.27	20.91%	890s	45,683	$5.12	$4.00
8th	Gemini 3.1 Pro (high)	73.36	58.46	20.31%	214s	25,905	$8.58	$11.83
9th	GPT-5.6 Luna (xhigh)	69.49	51.97	25.21%	242s	38,083	$6.31	$5.91
10th	DeepSeek V4 Pro (max)	68.00	49.97	26.51%	1468s	60,558	$1.45	$0.86
11th	Grok 4.5 (high)	67.59	56.72	16.08%	451s	43,372	$7.18	$5.91
12th	Muse Spark 1.1	66.18	57.23	13.52%	542s	42,416	$4.98	$4.19
13th	Gemini 3.5 Flash (high)	65.92	60.39	8.39%	188s	36,372	$9.03	$8.87
14th	Doubao-Seed-2.1-pro (high)	58.69	49.35	15.91%	2003s	85,059	$10.21	$4.29
15th	Qwen3.7-Plus (high)	58.50	44.09	24.63%	1237s	57,152	$1.83	$1.14
16th	Gemini 3.6 Flash (high)	56.87	41.74	26.6%	206s	26,329	$5.45	$7.39
17th	Tencent Hy3 (high)	54.42	44.60	18.04%	1035s	52,037	$0.83	$0.57
18th	Claude Sonnet 5 (xhigh)	51.37	43.14	16.02%	529s	44,118	$12.18	$9.86
19th	DeepSeek V4 Flash (max)	50.62	36.24	28.41%	611s	49,593	$0.40	$0.29
20th	MiniMax-M3	49.18	40.94	16.75%	985s	56,467	$1.90	$1.20
21st	Claude Opus 5	42.08	31.73	24.6%	154s	10,180	$7.02	$24.64
22nd	Claude Opus 4.6	36.88	25.79	30.07%	65s	4,387	$3.03	$24.64
23rd	Doubao-Seed-2.0-lite 0428 (high)	35.32	26.77	24.21%	656s	26,726	$0.38	$0.51
24th	Gemini 3.5 Flash (minimal)	33.24	22.22	33.15%	44s	6,189	$1.54	$8.87
25th	Ling-3.0-flash	32.53	20.62	36.61%	688s	86,204	$0.00	$0.00
26th	Gemini 3.5 Flash Lite (high)	30.23	22.82	24.51%	188s	18,297	$1.26	$2.46
27th	GPT-5.5 Instant	28.87	17.66	38.83%	25s	1,673	$1.39	$29.57
28th	Gemma 4 31B	27.91	22.04	21.03%	770s	15,050	$0.17	$0.39
29th	MiMo-V2.5-Pro	26.91	13.00	51.69%	478s	29,443	$0.71	$0.86
30th	Qwen3.7-Plus	26.19	16.23	38.03%	314s	8,692	$0.28	$1.14
31st	Step-3.7-Flash	26.18	13.74	47.52%	258s	44,912	$1.46	$1.16
32nd	Qwen3.5-27B	24.96	17.98	27.96%	451s	26,391	$0.51	$0.69
33rd	Gemini 3.1 Flash Lite (high)	23.78	14.30	39.87%	82s	28,351	$1.17	$1.48
34th	Claude Sonnet 5	23.64	10.86	54.06%	109s	5,962	$1.65	$9.86
35th	Qwen3.7-Max	22.45	18.53	17.46%	196s	6,710	$0.97	$5.14
36th	ERNIE 5.1	20.49	15.49	24.4%	457s	24,093	$1.73	$2.57
37th	openPangu-2.0-Flash	19.83	10.76	45.74%	571s	28,199	$0.18	$0.23
38th	LongCat-2.0	19.40	9.74	49.79%	395s	14,886	$0.48	$1.14
39th	DeepSeek V4 Flash	19.39	13.37	31.05%	63s	5,286	$0.04	$0.29
40th	Mistral Medium 3.5	18.44	13.87	24.78%	194s	27,854	$5.77	$7.39
41st	Doubao-Seed-2.1-pro	17.49	9.74	44.31%	305s	6,009	$0.72	$4.29
42nd	GLM-5.2	14.80	10.43	29.53%	23s	953	$0.11	$4.00
43rd	Ling-2.6-1T	13.05	8.39	35.71%	229s	4,770	$0.31	$2.29
44th	iFLYTEK Spark X2	12.39	6.21	49.88%	458s	11,285	$0.09	$0.29
45th	Gemini 3.1 Flash Lite	11.79	10.28	12.81%	9s	773	$0.03	$1.48
46th	Mistral Medium 3.5	10.83	7.13	34.16%	17s	2,546	$0.53	$7.39
47th	Ling-2.6-flash	10.07	4.85	51.84%	25s	4,997	$0.04	$0.30

Quick Start

Connect GPT-5.5 API without changing the OpenAI-style request shape. Use the reasoning controls for difficult coding and analysis, and reserve lower effort for interactive turns. The same endpoint supports file and image evidence without a separate multimodal API.

Get your API key

Create an APINEED key for GPT-5.5 API and keep it in an environment variable.

export API_NEED_API_KEY=sk-apineed-v1-...

Make your first request

Use gpt-5.5 for GPT-5.5 API with the APINEED API. The request shape is compatible with OpenAI chat completions, so most SDKs only need a base URL change.

TypeScript SDKPythoncURLOpenAI SDK

import OpenAI from "openai";

const client = new OpenAI({
  apiKey: process.env.API_NEED_API_KEY,
  baseURL: "https://apineed.com/v1"
});

const result = await client.chat.completions.create({
  model: "openai/gpt-5.5",
  messages: [
    { role: "user", content: "Why is the sky blue?" }
  ]
});

console.log(result.choices[0].message.content);

Enable streaming and fallbacks

Add stream: true when GPT-5.5 API should return server-sent events. APINEED keeps routing, provider health, and fallback handling behind the same endpoint.

curl https://apineed.com/v1/chat/completions \
  -H "Authorization: Bearer $API_NEED_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "openai/gpt-5.5",
    "stream": true,
    "messages": [{ "role": "user", "content": "Hello" }]
  }'

GPT-5.5 API Endpoint

GPT-5.5 API accepts chat conversations here with streaming or non-streaming text output; the supported controls are listed on this page.

POST/v1/chat/completions

Authorization: Bearer $API_NEED_API_KEY
Content-Type: application/json
HTTP-Referer: optional - your site URL, for rankings
X-Title: optional - your site name, for rankings
Model: openai/gpt-5.5

Parameters

GPT-5.5 API parameters currently listed for openai/gpt-5.5 by the OpenRouter Models API. ^[1]

Name	Type	Status	Description
`include_reasoning`	boolean	Supported	Includes reasoning content in the response when available.
`max_completion_tokens`	integer	Supported	Limits the combined visible and reasoning output tokens.
`max_tokens`	integer	Supported	Limits generated output tokens.
`reasoning`	object	Supported	Controls reasoning behavior and token allocation.
`reasoning_effort`	enum	Supported	Selects the model reasoning effort.
`response_format`	object	Supported	Requests a specific response format.
`seed`	integer	Supported	Requests deterministic sampling when supported by the provider.
`structured_outputs`	boolean	Supported	Enables schema-constrained structured output.
`tool_choice`	string or object	Supported	Controls which tool the model may call.
`tools`	array	Supported	Defines tools available to the model.

GPT-5.5 API Q&A

Model-specific answers for teams comparing GPT-5.5 API on capability, benchmark evidence, integration, and cost.

Why does GPT-5.5 API appear twice in the benchmark?

The table separates an xhigh reasoning run from GPT-5.5 Instant. They use different computation budgets and deliver very different rank and latency results.

What does the #1 result apply to for GPT-5.5 API?

It applies to the xhigh configuration in the July 2026 LLM2014 logic dataset, not every GPT-5.5 request or workload.

How should I control GPT-5.5 API cost?

Monitor output length and reasoning effort first, because the official output rate is six times the input rate and deeper runs may generate more tokens.

Can GPT-5.5 accept non-text evidence?

For GPT-5.5 API, yes. Its catalog record includes file, image, and text input with text output.

Which endpoint serves GPT-5.5 API?

Call GPT-5.5 API through https://apineed.com/v1/chat/completions with gpt-5.5 as the model value. Existing OpenAI SDK clients usually need only the APINEED base URL and key.

How do I validate GPT-5.5 API before release?

Evaluate GPT-5.5 API on representative prompts, record quality, latency, and token use, then choose reasoning settings and fallbacks from those results.

How to Deploy the GPT-5.5 API on apineed.com

Deploy GPT-5.5 API through APINEED after validating its model-specific trade-offs above. The API key, credit, and endpoint flow stays consistent across the catalog.

Add credits for GPT-5.5 API

Add credits on APINEED before deploying the GPT-5.5 API. Pay-as-you-go billing lets usage start small and scale with production traffic.

Get your API key

Create an APINEED API key for the GPT-5.5 API. The same key can call GPT-5.5 and other AI APIs through apineed.com.

Set the model slug

Use gpt-5.5 as the model value when you deploy the GPT-5.5 API. Keep the APINEED base URL at https://apineed.com/v1.

Send a request to GPT-5.5 API

Send chat completions or responses to the GPT-5.5 API from Claude Code, Codex, or any custom agent. The request keeps its OpenAI-compatible shape.

More models from OpenAI

GPT-5.6 Lunaopenai/gpt-5.6-luna GPT-5.6 Terraopenai/gpt-5.6-terra GPT-5.6 Solopenai/gpt-5.6-sol GPT-5.4openai/gpt-5.4