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...
Specifications
| Provider | OpenAI |
|---|---|
| Intelligence Index | Not yet benchmarked |
| Context window | 400,000 tokens (400K) |
| Input price | $1.25 / 1M tokens |
| Output price | $10 / 1M tokens |
| Input modalities | text, image |
| Output modalities | text |
| Model ID | openai/gpt-5.1-codex-max |
Pricing is per 1M tokens, indicative pricing via OpenRouter (updated 2026-10-05); a provider's own list price may differ. Intelligence Index via Artificial Analysis.
Frequently asked questions
How much does GPT-5.1-Codex-Max cost?
Indicative pricing (via OpenRouter, updated 2026-10-05) is $1.25 per 1M input tokens and $10 per 1M output tokens. A provider's own list price may differ. On Vincony, GPT-5.1-Codex-Max is available on credit-based pricing alongside 750+ other models.
What is GPT-5.1-Codex-Max's context window?
GPT-5.1-Codex-Max supports a context window of up to 400,000 tokens (400K), which is how much text it can consider at once.
Who makes GPT-5.1-Codex-Max?
GPT-5.1-Codex-Max is built by OpenAI. You can access it — and compare it against other providers' models — through Vincony's multi-model platform.
How do I use GPT-5.1-Codex-Max?
You can use GPT-5.1-Codex-Max directly through OpenAI, or via Vincony, which aggregates 750+ models (including GPT-5.1-Codex-Max) into one interface with side-by-side comparison and credit-based pricing.