Cloudflare’s 2025 year in review, covering 1 January to 2 December 2025 across its whole network, put search engine crawlers at 40% of verified bot traffic for the year and AI crawlers at half of that, 20%.1 Inside those categories the concentration is extreme rather than long-tailed: Googlebot alone drove over 28% of verified bot traffic, OpenAI’s GPTBot about 7.5%, and Microsoft’s Bingbot 6%.1 Four user agents carry most of what gets described as an army of crawlers.
Restricting the count to HTML, which is the traffic carrying your actual content, tightens the picture again. Across 2025 AI bots other than Googlebot averaged 4.2% of HTML requests on that network while Googlebot on its own accounted for 4.5%, and as of 2 December humans generated 47% of HTML requests against 44% for non-AI bots.1 More than nine HTML requests in ten had nothing to do with an AI crawler at all. A hosting platform’s own logs from a month in late 2024 reached the same shape by a different route, putting the two largest AI crawlers together at about 20% of Googlebot’s fetch volume in the same period.3
One caveat travels with every number here. Googlebot and Bingbot crawl for search indexing and for AI training at the same time, so whether they sit in the search bucket or the AI bucket is a labelling decision rather than a fact about the packets. Cloudflare counts Googlebot in both, which is why its AI crawler overview is headed by a bot most people would not call an AI crawler.1