A recent overview of computer navigation shows in the United States ChatGPT directed users to outside websites in 5.2% of sessionscompared to 31.1% for Google searches. The paper, led by researchers at Bocconi University, examines Comscore clickstream data to better understand the impact of broader access to ChatGPT on traditional search.
What the data shows
When people click on ChatGPT, they tend to visit a different set of websites than the visitors listed by Google. These are most often reference and knowledge sites, tools, SaaS platforms and academic or developer sites. Ad-supported sites account for 27.6 percentage points less of referral traffic.
Google referral traffic primarily points to popular destinations like YouTube, Reddit, and Wikipedia, while ChatGPT directs visitors more to smaller, specialized sites. The authors observe that ChatGPT tends to send people to nonprofit, subscription and freemium platforms, moving away from ad-supported sites that rely heavily on referrals.
The authors are cautious about the extent to which they should interpret this data, stating:
Our claim is deliberately narrower than a welfare claim: we measure a change in the observable distribution of traffic, not consumer surplus, publisher revenues, or long-term content production.
Researchers treat each conversation as a unique exchange and evaluate whether it led to an outbound click of its own. ChatGPT’s monthly referral rate increased from around 2.5% to almost 6.5% during the measurement period, although it remains lower than Google’s per-query rate.
What Wider Access Has Done to Research
OpenAI has gradually expanded access to ChatGPT Search: paid subscribers by October 2024; free users by December of the same year; and anonymous users by February 2025.
Wider access reduced traditional weekly search queries by 9.4%, with the reduction reaching 17% after 20 weeks. Comparing two groups already using ChatGPT, the decrease was 4.9% on average, increasing to 8.2% after 20 weeks.
The biggest drop was in searches for informational content, with references to academic research down 32.8% and references down 26.5%. Transactional and recreational searches have barely changed.
Why it matters
ChatGPT sends fewer referrals than Google and also directs people to different parts of the web. The most affected categories are academic, reference, developer, and news, although reference and knowledge sites are among the most common browsing contexts for ChatGPT.
SEJ covered Pew Research Center data showing that users click on links much less often when an AI summary is present, with most citations coming from a few major platforms. Bocconi’s article expands on this point, including estimates of how broader access has influenced the use of traditional research.
Looking to the future
The authors question whether content creators will continue publishing at the same scale when AI search uses their work but generates fewer hits. To answer this question, we need more than just US office data. We need mobile, international and revenue records to better understand the potential impact.
Featured Image: Jessica Rodriguez/Shutterstock
