Gemini 2.5 Pro starts as a thinking model

On 25 March 2025 Google DeepMind introduced Gemini 2.5. The first drop was Gemini 2.5 Pro Experimental — a “thinking” model for harder coding, math, and science. It shipped with a 1 million token context window (2 million promised).

It was in Google AI Studio and the Gemini app for Advanced users that day. Vertex AI and list prices came later. In June, Pro and Flash became generally available, and Flash-Lite arrived as the cheap, fast sibling.

Leaderboard rank is a preference score, not a warranty. Name the task you care about before you treat “most intelligent” as a fact.