March 16, 2026 — AI assistants comprise 56% of global search volume, according to a March 2026 analysis by Graphite.io CEO Ethan Smith, which found AI tools generate 45 billion monthly sessions worldwide, equivalent to 56% of search engine volume globally and 34% in the U.S.
The study, titled “AI Is Much Bigger Than You Think,” examined top AI assistants including ChatGPT, Gemini, Perplexity, Grok and Claude, revealing ChatGPT dominates with 89% of global AI sessions and 86% in the U.S. Notably, 83% of AI usage worldwide occurs in mobile apps, mostly Android, a factor previous web-only estimates underestimated by 4-5 times.
“Upon closer inspection of the data, we found that not only are the claims that AI may soon overtake search not overstated, they are understated.”
— Ethan Smith, Graphite.io CEO
Search-like “asking” prompts account for 28% of global search volume and 17% in the U.S., while total search usage combining engines and AI has grown 26% worldwide since 2023.
Implications for Marketers and SEO
AI assistants comprise 56% of global search volume, prompting marketers to adapt strategies beyond traditional Google rankings. Coverage in Search Engine Land (March 9, 2026) notes the need for both SEO and AI Engine Optimization (AEO), as Google’s search share fell from 89% in 2023 to 71% in Q4 2025.
Ignite Visibility (updated March 13, 2026) highlighted shifts to conversational and zero-click optimization, summarizing key stats in a table:
| Category | Global | U.S. |
|———————–|————|———–|
| Search Volume Share | 56% | 34% |
| Monthly Sessions | 45B | 5.4B |
| Mobile App Usage | 83% | 75% |
| ChatGPT Share | 89% | 86% |
The analysis debunks zero-sum views, stating AI growth is incremental to search.
Media Coverage
AI assistants comprise 56% of global search volume drew widespread attention. Performance Marketing World (March 10, 2026) reported AI usage growing faster than estimated, driven by mobile. ALM Corp echoed the 45 billion sessions figure.
Social Media Reaction
On X, Alex Hey (@heyalexhey) shared the findings on March 15, 2026, noting ChatGPT’s 90% AI market share and 83% mobile usage, linking to the Graphite.io article.
The study used Similarweb data for web visits and app sessions across top search engines and LLMs, adjusting for user intents per OpenAI research. AI assistants comprise 56% of global search volume underscores AI’s rising role without diminishing traditional search.