Google's Gemini 3.5 Pro, unveiled at Google I/O on May 19, is in limited preview for select Vertex AI enterprise customers and targeted for general availability, with Gemini 3.5 Flash already shipped and live as the default in the Gemini app and AI Mode in Search. The Pro model aims for a 2-million-token context window, Deep Think reasoning, and frontier multimodal capability.
As of mid-June, Pro had not yet shipped broadly to the public Gemini app or consumer subscription, and Sundar Pichai's 'wait another month' framing at I/O reportedly drew groans from a crowd hoping for immediate access. Launch windows can slip, so the timeline should be read as a target rather than a guarantee.
“The Pro model aims for a 2-million-token context window, Deep Think reasoning, and frontier multimodal capability.”
The stakes are competitive. With Anthropic reportedly capturing the majority of new enterprise AI spend and OpenAI pushing hard on deployment, Google needs a frontier-class Pro model to defend its position. A large context window and strong reasoning are exactly the capabilities enterprise buyers weigh when standardizing on a default model.