openai/gpt-5.1-codex-maxGPT-5.1-Codex-Max is OpenAI’s proprietary AI model, released Nov 19, 2025. It scores 150 on the Epoch Capabilities Index, costs $1.25/M input and $10/M output tokens, and handles a 400K-token context window.
GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks.
Scores on standardized evaluations. Higher is better — and rank shows where GPT-5.1-Codex-Max lands among all models tracked on Model Beat.
Autonomous task length
Command-line agentic tasks
GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks.
GPT-5.1-Codex-Max is an AI model developed by OpenAI, part of the GPT family, released Nov 19, 2025.
GPT-5.1-Codex-Max is served from $1.25 per million input tokens and $10 per million output tokens (cheapest credible provider on OpenRouter: OpenAI).
GPT-5.1-Codex-Max supports a context window of up to 400K tokens.
On standardized evaluations tracked by Epoch AI, GPT-5.1-Codex-Max scores 60.4% on Terminal-Bench, 3.7 h on METR task horizon.
GPT-5.1-Codex-Max is a proprietary model (API access), available through its provider's API rather than as a downloadable open-weight model.
Benchmark data from Epoch AI (CC BY) and Artificial Analysis; pricing, specs & descriptions from OpenRouter. Data updated Nov 12, 2026.