OpenAI: GPT-5.5 Pro
OpenAIllm
Published April 24, 2026
About
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 text and image inputs, and is designed for long-horizon problem solving, agentic coding, and precise execution across multi-step workflows.
Try OpenAI: GPT-5.5 Pro
Test this model in the Sandbase Playground with your own prompts.
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