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.
Modalities
In / out price
$30 / $180per 1M
Context
1.1M
Released
Apr 24, 2026
Knowledge cutoff
Dec 2025