← Back to explorer

OpenAI: GPT-5.1-Codex-Max

Server-rendered model summary page for indexing/share previews. Use the interactive explorer for full filtering and comparison.

Match confidence: UnmatchedSource type: openrouter_only
Context window
400K
Arena overall rank
Input price
$0.000 / 1M
Output price
$0.000 / 1M

Identifiers & provenance

Primary ID
openai/gpt-5.1-codex-max
OpenRouter ID
openai/gpt-5.1-codex-max
Canonical slug
openai/gpt-5.1-codex-max-20251204

Source semantics

  • Arena rank is a human-preference leaderboard signal, not a universal truth metric.
  • OpenRouter usage/popularity reflects adoption/traffic, not benchmark quality.
  • Pricing fields may differ by provider and can include extra modes beyond prompt/completion.

Read more on Methodology & data sources.

Description

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.

Raw fields snapshot

{
  "id": "openai/gpt-5.1-codex-max",
  "name": "OpenAI: GPT-5.1-Codex-Max",
  "description": "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. \nGPT-5.1-Codex-Max delivers faster performance, improved reasoning, and higher token efficiency across the development lifecycle. ",
  "created": 1764878934,
  "canonical_slug": "openai/gpt-5.1-codex-max-20251204",
  "hugging_face_id": "",
  "source_type": "openrouter_only",
  "context_length": 400000,
  "max_completion_tokens": 128000,
  "is_moderated": true,
  "architecture": {
    "modality": "text+image->text",
    "input_modalities": [
      "text",
      "image"
    ],
    "output_modalities": [
      "text"
    ],
    "tokenizer": "GPT",
    "instruct_type": null
  },
  "input_modalities": [
    "text",
    "image"
  ],
  "output_modalities": [
    "text"
  ],
  "modality": "text+image->text",
  "tokenizer": "GPT",
  "instruct_type": null,
  "supported_parameters": [
    "include_reasoning",
    "max_tokens",
    "reasoning",
    "response_format",
    "seed",
    "structured_outputs",
    "tool_choice",
    "tools"
  ],
  "default_parameters": {
    "temperature": null,
    "top_p": null,
    "frequency_penalty": null
  },
  "per_request_limits": null,
  "top_provider": {
    "context_length": 400000,
    "max_completion_tokens": 128000,
    "is_moderated": true
  },
  "pricing": {
    "prompt": "0.00000125",
    "completion": "0.00001",
    "web_search": "0.01",
    "input_cache_read": "0.000000125"
  },
  "PPM": {
    "prompt": 1.25,
    "completion": 10,
    "web_search": 10000,
    "input_cache_read": 0.125
  },
  "openrouter_raw": {
    "id": "openai/gpt-5.1-codex-max",
    "canonical_slug": "openai/gpt-5.1-codex-max-20251204",
    "hugging_face_id": "",
    "name": "OpenAI: GPT-5.1-Codex-Max",
    "created": 1764878934,
    "description": "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. \nGPT-5.1-Codex-Max delivers faster performance, improved reasoning, and higher token efficiency across the development lifecycle. ",
    "context_length": 400000,
    "architecture": {
      "modality": "text+image->text",
      "input_modalities": [
        "text",
        "image"
      ],
      "output_modalities": [
        "text"
      ],
      "tokenizer": "GPT",
      "instruct_type": null
    },
    "pricing": {
      "prompt": "0.00000125",
      "completion": "0.00001",
      "web_search": "0.01",
      "input_cache_read": "0.000000125"
    },
    "top_provider": {
      "context_length": 400000,
      "max_completion_tokens": 128000,
      "is_moderated": true
    },
    "per_request_limits": null,
    "supported_parameters": [
      "include_reasoning",
      "max_tokens",
      "reasoning",
      "response_format",
      "seed",
      "structured_outputs",
      "tool_choice",
      "tools"
    ],
    "default_parameters": {
      "temperature": null,
      "top_p": null,
      "frequency_penalty": null
    },
    "expiration_date": null
  }
}
OpenAI: GPT-5.1-Codex-Max · NNZen