GPT-5.1-Codex-Max
OPENAI Developer Architecture Profile
Intelligence (ELO)1300Chatbot Arena Verified
Max Context400,000Tokens
API Cost / 1M$11.25Blended Prompt + Completion
Model Capabilities
- Coding & Logic
- Fictional
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.
Granular Pricing Matrix
Input Tokens (Prompt)$1.25 / 1M
Output Tokens (Completion)$10.00 / 1M
Pricing data via OpenRouter. Sync: 3/16/2026
Evaluate Competitors
VS Engine MatchupGPT-5.1-Codex-Max vs Google: Nano Banana 2 (Gemini 3.1 Flash Image Preview)VS Engine MatchupGPT-5.1-Codex-Max vs Google: Gemini 3.1 Pro Preview Custom ToolsVS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.2-CodexVS Engine MatchupGPT-5.1-Codex-Max vs Google: Gemini 3 Flash PreviewVS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.2 ProVS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.2