OpenAI Gaining Market Share in AI Tools, With Google a Far Second

OpenAI’s artificial intelligence (AI) tools showed a surge in website traffic in the past two months, with Google a distant second and DeepSeek catching up quickly.

According to new data from Similarweb, which tracks website traffic, daily average visits to ChatGPT and other OpenAI application programming interface (API) sites markedly jumped in April and continued to climb through May 9, the latest date tracked.

From late March to early May, traffic rose 27% from around 150 million visits to 190 million for OpenAI.

By May 9, OpenAI’s platforms accounted for an estimated 190 million of the 240 million daily average visits to all AI platforms.

That’s nearly 80% of all generative AI tool traffic, underscoring OpenAI’s network effects, model performance and branding strength.

Notably, OpenAI reversed a decline that began in November, which fell from about 150 million to around 120 million.

Read more: Analysts: Google Search Traffic ‘Stable’ Despite Surge of AI Chatbots Use

DeepSeek and Grok Are Surprise Gainers

Similarweb said it defines general AI tools as those performing a wide variety of automation tasks that “incorporate the interpretation of human language and generate responses and insights” usually through a chat or search user interface.

Traffic is an important signal not just of user interest, but of ecosystem strength, monetization potential and future platform consolidation.

For now, OpenAI reigns supreme. Even during a January lull due to post-holiday seasonality, OpenAI maintained its position as the category leader.

OpenAI’s aggressive product updates, GPT-4o releases and integration into enterprise workflows via Microsoft partnerships appear to have solidified its lead.

Google is second, with traffic remaining relatively unchanged at about 25 million daily average visits during the period, despite the rollout of Gemini-powered tools across Search and Workspace.

This suggests that while Gemini may be integrated widely, it has yet to become a destination AI product in its own right.

However, in April, Gemini was one of only two generative AI platform to see an uptick after Google unveiled Gemini 2.5, according to Similarweb. The other one seeing growth was ChatGPT.

The most striking trend in the latter part of the timeline is the rise of DeepSeek and Grok, with Perplexity remaining steady.

DeepSeek, a Chinese open-source large language model provider, burst onto the leaderboard in January and is gaining on Google Gemini with about 20 million daily average visits. The fast acceleration underscores demand for open, customizable and potentially cheaper alternatives, especially in Asia.

Grok, from Elon Musk’s xAI startup, saw fast growth starting in late February, thanks to Grok 3’s release, according to Similarweb. It had around eight million daily average visits.

Perplexity, which is known for its source links, was relatively steady at five million despite its marketing blitz about new capabilities.