Last Updated: September 11, 2026
Our team tracked the generative AI chatbot market share across major AI platforms. For this study, “generative AI chatbot” refers to LLM-based web and mobile applications that the public uses to seek answers or create content. All figures are estimated based on monthly active users across U.S. web and mobile platforms.
The Top Generative AI Chatbots by Market Share – September 2026
| Rank | Generative AI Chatbot | Description | Included LLMs | AI Chatbot Market Share |
| 1 | ChatGPT | General-purpose AI chatbot | GPT-5.5 Instant,GPT-5.5 Thinking,GPT-5.5 Pro | 51.5% |
| 2 | Google Gemini | General-purpose AI assistant | Gemini 3.5 Flash, Gemini 3.1 Pro, Gemini 3 Deep Think | 27.6% |
| 3 | Claude AI | Business-focused AI assistant | Claude Opus 4.8, Claude Sonnet 4.6, Claude Haiku 4.5, Claude Fable 5, Claude Mythos 5 | 10.2% |
| 4 | Other | Specialized, regional, and emerging AI chatbots | Mistral Le Chat (Magistral/Mistral Medium), Qwen Chat (Qwen 3), Amazon Rufus, Character.AI | 4.2% |
| 5 | Grok | General-purpose AI assistant | Grok 4.3, V9-Medium, Grok Build | 2.8% |
| 6 | Perplexity | Accuracy-focused AI chatbot | Sonar, Sonar Pro, Sonar Reasoning Pro, Kimi K2.5 | 2.0% |
| 7 | Microsoft Copilot | General-purpose AI assistant | GPT-5.5, GPT-5.3, Claude Sonnet 4.6 | 1.3% |
| 8 | DeepSeek | General-purpose AI assistant | DeepSeek V4 (Pro/Flash), DeepSeek V3.2 | 0.4% |
| 9 | Meta AI | Social platform-embedded AI assistant | Muse Spark | 0.1% |
ChatGPT still dominates U.S. usage, holding a larger share than all other chatbots combined. Google Gemini and Claude follow at a distance, but together the top three account for the overwhelming majority of the market, which shows how concentrated AI usage remains despite the steady flow of new AI platforms. Among these, Grok has maintained relatively steady usage that has come to outpace Perplexity over the last couple months. Nonetheless, it is still far behind the leading platforms.
The defining trend is fragmentation. The AI assistant space is splitting into multiple tools instead of one program dominating. ChatGPT is still in the front, but its lead has narrowed recently, as users are picking up other tools alongside it. If that pattern continues, ChatGPT’s share is predicted to keep declining. That said, some projections suggest that ChatGPT will plateau in the 50–55% range as more casual users migrate while its core base remains, making a full collapse unlikely.
The Fastest Growing Generative AI Chatbots
The following table ranks generative AI chatbots by their quarterly change in estimated users. While most of this quarter’s growth was driven by product launches, that momentum typically flattens once the launch cycle ends.
Fastest Growing Generative AI Chatbots – September 2026
| Rank | Generative AI Chatbot | Estimated Quarterly User Growth |
| 1 | Google Gemini | +17% ▲ |
| 2 | Claude AI | +14% ▲ |
| 3 | DeepSeek¹ | +7% ▲ |
| 4 | ChatGPT | +4% ▲ |
| 5 | Grok² | +4% ▲ |
| 6 | Perplexity² | +4% ▲ |
| 7 | Microsoft Copilot | +3% ▲ |
| 8 | Meta AI³ | Verified numbers not available |
¹DeepSeek posted the quarter’s most notable growth relative to its size, driven by the April 24 launch of DeepSeek V4, an affordable open-source frontier model. That cost efficiency is attracting developers and organizations priced out of proprietary alternatives.
²Grok and Perplexity remain well behind the top platforms in absolute scale.
³Meta AI’s numbers remain unverifiable as a standalone chatbot. Its user count includes passive social feed interactions across WhatsApp, Instagram, and Facebook, which are not comparable to active chatbot sessions.
ChatGPT Market Share: 2026 Trend
The following table displays the trend in ChatGPT’s market share during the year 2026 in the generative AI chatbot industry. Being the pioneer and market leader, ChatGPT has the most to lose, and its market share has continued to decline as it faces increasing competition from other chatbots. On the bright side, the platform still managed to grow by 4% this quarter, thanks to the rollout of GPT-5.5 Instant as the default model. The launch may help ChatGPT maintain its core user base and limit further market-share losses in the months ahead.
NOTE: ChatGPT’s market share includes that of Bing’s Copilot product, as they both use the same underlying system; the difference is only that Microsoft Copilot personalizes ChatGPT based on user data in the Microsoft ecosystem.
| Month | ChatGPT Market Share |
| January 2026 | 67.1% |
| February 2026 | 65.7% |
| March 2026 | 62.6% |
| April 2026 | 61.8% |
| May 2026 | 59.1% |
| June 2026 | 58.6% |
| July 2026 | 51.3% |
| August 2026 | 51.5% |
Microsoft Copilot Market Share: 2026 Trend
Microsoft Copilot’s market share followed a classic dip-and-recovery arc through the first half of 2026. Although Copilot posted the quarter’s slowest growth at +3%, its trajectory improved over that period, with momentum picking up in early summer, due to Scout launching at Build, Copilot Cowork reaching general availability, and Claude becoming available in select Copilot experiences.
| Month | Copilot Market Share |
| January 2026 | 1.15% |
| February 2026 | 1.13% |
| March 2026 | 1.11% |
| April 2026 | 1.17% |
| May 2026 | 1.21% |
| June 2026 | 1.25% |
| July 2026 | 1.30% |
| August 2026 | 1.30% |
Google Gemini Market Share: 2026 Trend
Google Gemini opened the year roughly flat. In May, Google introduced Gemini Spark, an always-on agentic assistant, and cut the entry price of its AI Ultra tier to $99.99 a month to broaden access. As a result, Gemini made a significant leap from June to July, most likely because of its integration with Android devices and Gmail. As of August 2026, Google Gemini has over a billion monthly active users.
| Month | Gemini Market Share |
| January 2026 | 14.0% |
| February 2026 | 14.1% |
| March 2026 | 13.8% |
| April 2026 | 13.2% |
| May 2026 | 13.5% |
| June 2026 | 13.3% |
| July 2026 | 27.7% |
| August 2026 | 27.6% |
Perplexity Market Share: 2026 Trend
Perplexity gave up a good chunk of ground through early 2026, as larger, more general-purpose AI assistants integrated answer and search features into their own apps, diminishing the advantage of a standalone answer engine. The decline has continued, leaving Perplexity’s user base well below where it began the year, even though its enterprise and revenue base has kept growing.
| Month | Perplexity Market Share |
| January 2026 | 5.3% |
| February 2026 | 4.0% |
| March 2026 | 3.4% |
| April 2026 | 2.8% |
| May 2026 | 2.7% |
| June 2026 | 2.6% |
| July 2026 | 2.0% |
| July 2026 | 2.0% |
| August 2026 | 2.0% |
ClaudeAI Market Share: 2026 Trend
Claude’s share dipped from 11.5% in June to 10.3% in July. The June 9 launch of Claude Fable 5 and Claude Mythos 5 helped support momentum, although Anthropic disabled both models on June 12 under a U.S. export-control directive. Fable 5 access was restored on July 1, while Mythos 5 remains restricted.
The July dip may be due to the intensifying competition rather than a weakening demand. As ChatGPT, Gemini, Grok, and other AI assistants release new models and capabilities almost daily, users might be testing out features and compatibility across multiple platforms rather than focusing on a single platform.
| Month | Claude AI Market Share |
| January 2026 | 8.5% |
| February 2026 | 9.6% |
| March 2026 | 8.9% |
| April 2026 | 8.2% |
| May 2026 | 8.9% |
| June 2026 | 11.5% |
| July 2026 | 10.3% |
| August 2026 | 10.2% |
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