ChatGPT remains the largest AI chatbot by web visits, but the gap has narrowed. In April 2026, Similarweb data compiled by Momentic put ChatGPT at 54.7% of visits across seven major AI chat services, down from 76.5% two years earlier.
What changed
Gemini is the main challenger. Its global share reached 27.4%, up from 5.6% a year earlier and up 104% over the most recent six months. ChatGPT and Gemini together now account for about 82% of measured visits.
What to watch
Claude is growing faster from a smaller base. Its visits rose about 306% in one quarter, from 203 million in January to 824 million in April, giving it 8.2% globally and 12.5% in the United States. The chart does not include mobile app usage, embedded assistants or API traffic, so it is a web signal rather than a full business scorecard.
Sources：Momentic and Similarweb data on generative AI chatbot market share；CocoLoop