GPT-5.1-Codex-Max
by OpenAI
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.
Capabilities
Pricing
Input Tokens
Per 1M tokens
Free
Output Tokens
Per 1M tokens
Free
Image Processing
Per 1M tokens
$0.00/1M tokens
Supported Modalities
Input
text
image
Output
text
Specifications
- Context Length
- 400K tokens
- Provider
- OpenAI
- Released
- Dec 4, 2025
- Model ID
- openai/gpt-5.1-codex-max
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