Market Share Decline for ChatGPT
According to a 2026 report from Sensor Tower, ChatGPT's share of the AI assistant market fell below 50% for the first time, landing at 46.4% in May. This decline is driven by the rise of competitors like Gemini, which holds 27.7%, and Claude, with 10.3%. Users are increasingly switching between different assistants, a trend highlighted by Sensor Tower representatives:
“This happened because users are moving between various assistants” - Sensor Tower
ChatGPT remains popular, with over 1.1 billion monthly users. However, its competitors are also showing strong numbers: Gemini boasts 662 million users, and Claude has 245 million. As of January 2026, ChatGPT's share was above 50%, but it dropped by the end of May. Other assistants like Grok, Perplexity, DeepSeek, and Meta AI each hold less than 5% of the market. The top three assistants together account for 89% of all time spent on AI assistants.
Market Expectations for AI
In the first half of 2026, AI app downloads are projected to reach 2.3 billion, with spending exceeding $4.2 billion. This marks significant growth compared to the first half of 2025, when AI app spending was $1.83 billion. Hours spent using AI apps are expected to rise from 17.2 billion in the first half of 2025 to 36 billion in the first half of 2026.
For the first time, Asia saw a 3.3% drop in downloads in the first quarter of 2026. These market shifts indicate that users value not only features but also brand trust and value alignment, according to Sensor Tower. Meanwhile, OpenAI, the company behind ChatGPT, signed a deal with the U.S. Department of Defense (DoD) in February 2026.
In light of these changes, the Florida Attorney General filed a civil lawsuit against OpenAI and Sam Altman, accusing the company of achieving growth through deception and user exploitation. The lawsuit underscores the complex and tense landscape of the artificial intelligence market.
- ChatGPT's declining market share reflects growing competition in the AI space.
- New players like Gemini and Claude are gaining traction.
- Shifts in user preferences may highlight the importance of brand trust.
- The lawsuit against OpenAI points to legal challenges the company faces.
As the competitive landscape of AI assistants evolves, OpenAI is actively seeking to enhance ChatGPT's functionality by transforming it into a comprehensive all-in-one AI solution. This strategic shift may play a crucial role in regaining market share and addressing user preferences for diverse capabilities and trust in AI technologies.