OpenAI’s ChatGPT is facing a significant deceleration in user growth, according to fresh market intelligence from Sensor Tower. While the platform remains the market leader—commanding 50% of global mobile downloads and 55% of monthly active users—Google’s Gemini is rapidly eroding that dominance by outpacing ChatGPT in download rates, active user expansion, and daily engagement.
The Battle for AI Supremacy
The intensifying rivalry has caught the attention of OpenAI leadership. CEO Sam Altman reportedly issued a “code red” internal memo, directing staff to prioritize enhancements in reliability, personalization, and image generation. This strategic pivot aims to fortify ChatGPT’s position as competitors successfully chip away at its market share.
Data from November 2025 highlights the diverging paths of the two giants. While ChatGPT saw a 180% year-over-year climb in monthly active users, Gemini followed closely with 170% growth. However, the short-term trends paint a different picture: between August and November 2025, ChatGPT’s active user base grew by only 6%, reaching approximately 810 million—a figure analysts suggest may indicate market saturation.
Google’s Strategic Advantage
Conversely, Gemini experienced a 30% jump in active users during that same three-month window. A major catalyst for this surge was the launch of the “Nano Banana” image generation model. Beyond feature updates, Google holds a structural advantage: U.S. Android users are twice as likely to engage with Gemini directly through the operating system rather than the standalone app. This deep integration allows Gemini to bypass the constraints of traditional mobile app usage, providing a significant edge in the global Android-dominated market.
Market Share and Competitive Pressure
Over the seven-month period ending in November 2025, Gemini increased its share of the global AI chatbot market by three percentage points. In contrast, ChatGPT’s share dropped by three percentage points between August and November. The competitive landscape is further crowded by aggressive challengers like Perplexity and Claude, which reported year-over-year growth of 370% and 190%, respectively.
Engagement metrics also signal a shifting tide. Gemini users now spend an average of 11 minutes per day in the app—a 120% increase since March. Meanwhile, ChatGPT’s daily engagement saw a modest 6% increase in the same timeframe, with November usage actually dipping 10% compared to July. While Google’s momentum is currently fueled by the success of its new models, the race remains fluid; OpenAI’s ability to regain its growth trajectory will depend on the market impact of its upcoming product pipeline.