Model page
Grok-4.1 Fast Reasoning
Fast reasoning variant of Grok-4.1 with enhanced logical capabilities.
Key dates
We use concrete dates and keep them consistent across the site.
ChatGPT
GPT‑4o retirement (ChatGPT)
OpenAI is retiring GPT‑4o inside ChatGPT on February 13, 2026. This does not automatically imply API removal.