GoogleapiGemini 2.5 Pro and 2.5 Flash Retirement
Google is phasing out two older Gemini models in AI Studio and the API, which matters to anyone with a custom tool or automation still calling them.
Details
- Both models can no longer be selected in Google AI Studio, and API access is limited to users who have used them before.
- From December 1, 2026, requests to gemini-2.5-pro route to gemini-3.8-flash and requests to gemini-2.5-flash route to gemini-3.5-flash-lite, billed at the new model's rates.
- Swapping the model name alone may not be enough. Google lists breaking changes around function calling validation, thinking settings, sampling parameters, and prefilled model turns.
- gemini-2.5-flash-lite is not deprecated and has no shutdown date.
Best for
Checking custom tools and automations built on older Gemini models before they change behavior and pricing.
When to use it
Anything your team built names gemini-2.5-pro or gemini-2.5-flash as its model.
Who benefits
Developers, plus whoever owns a custom automation or internal tool that calls the Gemini API.
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