Google announced on November 2 that Gemini 2.5 Pro (gemini-2.5-pro) and Gemini 2.5 Flash (gemini-2.5-flash) are deprecated and no longer selectable in Google AI Studio. Remaining API access is limited to existing users who previously used these models. From December 1, 2026, Pro requests will automatically route to gemini-3.8-flash, while Flash requests will route to gemini-3.5-flash-lite, with billing at the replacement models' rates.
The transition changes more than the model behind an endpoint. Google lists breaking changes to function calling, reasoning controls, sampling parameters, and prefilled model turns, and recommends reviewing migration guidance before the switch. Gemini 2.5 Flash-Lite (gemini-2.5-flash-lite) is not deprecated and remains available through the API.
Source · aistudio.google.com ↗
