ChatGPT's AI Assistant Market Share Drops Below 50% for First Time
OpenAI's grip slips to 46.4% as Claude grows 640% year-over-year.
OpenAI's ChatGPT has lost its majority grip on the AI assistant market for the first time, according to a Sensor Tower report cited by TechCrunch. As of May 31, ChatGPT's share dropped to 46.4%, down from over 50% at the start of 2025. Google Gemini commands 27.7%, while Anthropic's Claude holds 10.3% but boasts an explosive 640% year-over-year monthly active user growth, compared to ChatGPT's 62%. Grok, Perplexity, MetaAI, and DeepSeek collectively make up just 5%.
The decline accompanies a turbulent year for OpenAI: a controversial Pentagon deal (acknowledged as 'opportunistic' by CEO Sam Altman), the rise of the QuitGPT boycott claiming 4 million participants, the killing of its Sora video app, and the introduction of ads. Anthropic's enterprise surge triggered an internal 'code red' at OpenAI, pushing a strategy pivot to productivity. Meanwhile, OpenAI won its legal battle with Elon Musk, a rare bright spot. The data suggests that even a market leader can lose dominance when brand perception sours and competitors like Anthropic grow faster.
- ChatGPT's AI assistant market share fell to an all-time low of 46.4% in May, down from >50% earlier in 2025.
- Anthropic's Claude grew monthly active users by 640% year-over-year, reaching 10.3% share; Google Gemini holds 27.7%.
- OpenAI's Pentagon deal, ad rollout, Sora shutdown, and QuitGPT boycott (4M members) contributed to brand erosion.
Why It Matters
OpenAI's slipping dominance signals that AI assistant markets are still fluid; brand trust and enterprise focus are now critical competitive differentiators.