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.
Context Window
400K
Input Price
$1.25/M tokens
Output Price
$10.00/M tokens
Modality
text+image->text
Cost Example: Processing 10,000 input tokens and generating 1,000 output tokens would cost approximately $0.022500
~300K
Words Equivalent
~200
Pages of Text
~4000
Code Functions
Related Categories:
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