What is OpenAI: GPT-5.5's context window?

OpenAI: GPT-5.5 supports a context window of 1,050,000 tokens, allowing you to process large documents and maintain long conversations.

How to use OpenAI: GPT-5.5 API via Ofox?

Simply set your base URL to https://api.ofox.run/v1 and use your Ofox API key. The API is OpenAI-compatible — just change the base URL and API key in your existing code.

OpenAI: GPT-5.5

Name: OpenAI: GPT-5.5
Brand: openai
Price: 5 USD
Availability: InStock
Rating: 5 (1 reviews)

Chat

openai/gpt-5.5

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GPT-5.5 is OpenAI's frontier model for complex professional workloads, released on 2026-04-24, building on GPT-5.4 with stronger reasoning, higher reliability, and better token efficiency on hard tasks. It takes text and image input and supports tool use (function calling), prompt caching, and web search, enabling large-scale reasoning, coding, and multimodal workflows in a single system. Context: 1M+ tokens (922K input), output: 128K. Available via OpenAI and Anthropic protocols.

Context Window

Max Output Tokens

128K

Released

2026-04-24

Capabilities

VisionFunction CallingReasoningPrompt CachingWeb Search

Available Providers

Azure

Supported Protocols

openaianthropic

Providers

Azure

Input Tokens

$5/M

Output Tokens

$30/M

Cache Read

$0.5/M

Output Image

$32/M

Web Search

$0.035/R

Protocols

openai/v1/chat/completions/v1/responses

anthropic

Code Examples

from openai import OpenAI

client = OpenAI(
    base_url="https://api.ofox.run/v1",
    api_key="YOUR_OFOX_API_KEY",
)

response = client.chat.completions.create(
    model="openai/gpt-5.5",
    messages=[
        {"role": "user", "content": "Hello!"}
    ],
)

print(response.choices[0].message.content)

Uptime & Status

Benchmarks

LMArena ↗Evaluated as gpt-5.5

OpenAI: GPT-5.5 scores 1474 in the Overall category of the LMArena text leaderboard (style control), ranking #20 of 374 models based on 43,495 human preference votes (updated 2026-07-12).

Benchmark scores for gpt-5.5 on LMArena
Category	95% CI	Rank	Votes
Overall	1470–1479	#20 of 374	43,495
Hard Prompts	1487–1498	#24 of 374	28,643
Coding	1499–1513	#41 of 369	12,337
Math	1484–1510	#8 of 362	2,241
Creative Writing	1439–1455	#28 of 372	7,503
Instruction Following	1464–1477	#18 of 374	14,622
Chinese	1519–1548	#6 of 344	2,065

Source: LMArena · CC BY 4.0 · Updated 2026-07-12 · Methodology ↗ · Ranks compare models within each category of the LMArena text leaderboard (style control). Scores come from third-party human preference evaluations, not from OFOX.