OpenAI: GPT-5.1-Codex-Max
GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks. It is based on an updated version of the 5.1 reasoning stack and trained on agentic workflows spanning software engineering, mathematics, and research. GPT-5.1-Codex-Max delivers faster performance, improved reasoning, and higher token efficiency across the development lifecycle.
Undisclosed
Parameters
400K tokens
Context Window
Proprietary
License
Dec 4, 2025
Released
💰 Pricing
Input
$1.25
per 1M tokens
Output
$10.00
per 1M tokens
API Available
This model is accessible via API for integration into your applications.
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