The paper “Browsing behavior exposes identities on the Web” by Marcos Oliveira and colleagues has been published in Nature Scientific Reports, 15, 36066 (2025). The study shows that people’s web browsing habits act as behavioral fingerprints: just the four most visited websites are enough to uniquely identify 95% of individuals. These fingerprints are stable enough to re-identify 80% of users across different time periods, highlighting a significant and underexplored privacy risk rooted in everyday online routines.