Deep Think API is an advanced reasoning capability integrated into Google's Gemini 3 Pro model. It enables extended, multi-step logical processing for complex problems. Unlike standard AI inference that provides immediate responses, Deep Think breaks down challenges into structured reasoning steps, evaluates multiple solution paths, validates its logic, and presents transparent thinking processes. Google DeepMind created Deep Think to tackle problems requiring creativity, strategic planning, and step-by-step improvements. It can intelligently detect when a query benefits from deeper reasoning and suggest activating Deep Think mode.
Deep Think is designed for tasks requiring deep analysis, such as complex planning, multi-module debugging, research synthesis, and strategic decision-making where accuracy and reasoning depth are more important than response speed. Gemini 3 Deep Think leverages Gemini 3 Pro's full 1 million token context window. It is available to Google AI Ultra subscribers. The Google AI Ultra plan costs $249.99 per month. Access to Gemini 2.5 Deep Think was initially limited to the Gemini app and web interface for Ultra subscribers. However, Google has been working to release Deep Think with and without tools to trusted testers via the Gemini API. As of February 2026, Deep Think is available via the Gemini API to select researchers, engineers, and enterprises.
