AI tools now generate 45 billion monthly sessions worldwide — about 56% of search engine volume, according to a study by Graphite.io CEO Ethan Smith.
The analysis combines web traffic and mobile app usage across major AI tools and estimates AI activity equals 56% of global search usage and 34% in the U.S.
Much of this growth is occurring in mobile apps such as ChatGPT, Gemini, Perplexity, Grok, and Claude.
Why we care. AI is expanding discovery, not shrinking search demand. Total usage across search engines and AI assistants has grown 26% globally since 2023. In other words, it’s not SEO vs. GEO — you need both LLM visibility and traditional rankings.
The details. The report analyzed usage across the five largest LLM products — ChatGPT, Gemini, Perplexity, Grok, and Claude — and compared them with the six largest search engines. Key findings:
AI platforms generate 45 billion monthly sessions worldwide.
In the U.S., AI accounts for 5.4 billion monthly sessions.
83% of global AI usage occurs inside mobile apps (75% in the U.S.).
ChatGPT dominates AI usage, representing 89% of global AI sessions.
When isolating search-like prompts (“asking”), AI usage equals 28% of search worldwide and 17% in the U.S.
The report excludes prompts categorized as “doing” or “expressing.” According to OpenAI research, about 52% of prompts are information-seeking, the closest equivalent to traditional search queries.
Between the lines. Most projections comparing AI to search use web traffic alone, typically comparing Google.com visits with ChatGPT website traffic. That misses most AI usage.
The analysis argues these comparisons underestimate AI activity by 4–5x because most usage occurs in mobile apps.
It also includes multiple LLMs and multiple search engines rather than comparing only Google and ChatGPT.
What to watch. Google still dominates discovery, but its share of search-related activity fell from 89% in 2023 to 71% in Q4 2025, the report estimates.
Global AI usage appears to have plateaued since July 2025, while U.S. usage continues to grow rapidly — up roughly 300% year over year by December 2025.
The report. AI Is Much Bigger Than You Think