GPT-5.1-Codex-Maxon Krater.ai
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
Released December 4, 2025
Specifications
GPT-5.1-Codex-Max at a glance
Context
400K tokens
Max output
128K tokens
Input
Text, Image
Output
Text
Input price
$1.25 / 1M
Output price
$10.00 / 1M
Capabilities
What it is good at
Catalog capabilities
- Accepts image input
- Generates text responses
- Supports tool calling
- Supports structured outputs
Good for
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Compare GPT-5.1-Codex-Max
GPT-5.1-Codex-Max vs GPT-5.1-Codex
GPT-5.1-Codex is a specialized version of GPT-5.1 optimized for software engineering and coding workflows.
Open comparisonGPT-5.1-Codex-Max vs GPT-5.2 Codex
GPT-5.2-Codex is an upgraded version of GPT-5.1-Codex optimized for software engineering and coding workflows.
Open comparisonGPT-5.1-Codex-Max vs GPT-5 Codex (batch)
GPT-5-Codex is a specialized version of GPT-5 optimized for software engineering and coding workflows.
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