Google's Gemini tripled its generative AI market share to 18.2% over the past 12 months, cutting ChatGPT's dominance from 87.2% to 68.0%. Similarweb data shows the 19-point shift marks Google's transition from AI contender to serious challenger.
Analytics platform Similarweb tracked Gemini's rise from 5.4% to 18.2% share between December 2024 and December 2025. ChatGPT dropped 19 percentage points during the same period, according to the web traffic analysis.
Solid Finance CEO Sam Badawi called the shift definitive. "If you believe web behavior reflects user preference at scale, then this is the clearest signal that Google is not only in the game, it is winning share," Badawi told The Financial Express.
Gemini's growth stems from Google's ecosystem integration strategy. The AI assistant surfaces directly within Chrome, Android, Search, and Workspace tools like Gmail and Docs. This native distribution captures users where questions happen rather than requiring separate app navigation.
Microsoft's Copilot demonstrates that distribution alone doesn't guarantee success. Despite being baked into Windows and Edge, Copilot's share barely moved from 1.5% to 1.2% over the same period. The contrast reveals that being preinstalled puts AI in front of users but still requires earning repeat engagement.
Regional data from Romania shows similar patterns. ChatGPT maintained over 85% market share there throughout 2025, according to SEO agency Mixtazure. But Gemini entered the top three AI tools with sharp growth in August and September.
Nearly 60% of Romanian respondents now use AI chats more often than traditional search engines. Generation Z and Millennials aged 20 to 39 are the most active users, with most integrating AI into both personal and professional activities.
Alphabet's stock performance reflects investor confidence in the AI strategy. Class C shares rose 65.59% year-to-date, far outpacing the Nasdaq 100's 22.31% gain. The stock gained 80.97% over the last six months.
The shift represents a fundamental change in how users interact with AI. As generative AI transitions from novelty to routine utility, products embedded in daily workflows naturally capture usage. Gemini meets users where work already happens across Google's ecosystem.
Industry observers note the broader implications. When AI becomes a daily habit rather than occasional experiment, convenience outweighs standalone capability. Google's infrastructure advantage positions Gemini to continue gaining ground as AI integration deepens.
The data suggests a maturing market where early dominance gives way to platform-based competition. ChatGPT remains the largest player, but Gemini's triple-digit growth indicates users are spreading AI usage across multiple tools based on workflow integration.
