GPT-5.5 Pro reasoning

openrouter
openai
GPT-5.5 Pro is OpenAI’s high-capability model optimized for deep reasoning and accuracy on complex, high-stakes workloads. It features a 1M+ token context window (922K input, 128K output) with support for...

Capabilities

Context Window 1M tokens
Max Output 128k tokens
Inputs
Outputs

Pricing (per 1M tokens)

Input $30.00
Output $180.00
Cache Read -
Cache Write -

Supported Parameters

include_reasoningmax_tokensreasoningresponse_formatseedstructured_outputstool_choicetools