o1 Pro
by OpenAI
Premium reasoning model applying maximum compute for deeper thinking and most consistent results. Built for the highest reliability standards with extensive reasoning time, designed for mission-critical applications requiring ultimate accuracy.
- Maximum compute application using extensive resources for deepest possible reasoning
- Ultimate reliability standard designed for mission-critical applications requiring highest accuracy
- Extended thinking time providing the most thorough analysis and consistent results
- Premium problem-solving capability excelling on the most challenging mathematical and scientific problems
- Highest-tier performance representing the peak of OpenAI's reasoning model capabilities
Model Information
Supported Formats
GPT 5.5OpenAI's most advanced model released April 2026. GPT-5.5 is recommended for most reasoning workloads, combining frontier intelligence with configurable reasoning effort (none → xhigh). Available in API, Codex, and ChatGPT.
GPT 5.5 ProHighest-intelligence API option in the GPT-5.5 family. Use for the most challenging problems that require maximum reasoning depth and can tolerate higher latency. Supports full reasoning effort range from none to xhigh.
GPT 5.4GPT-5.4 is OpenAI's frontier model for complex professional work, designed for agentic, coding, and professional workflows with the highest reasoning capability. Features a 1.05M token context window, native computer use, and built-in support for web search, file search, and MCP.