For you vs. for everyone: The effectiveness of algorithmic personalization in driving social media engagement

• This study investigated the effects of algorithmic personalization on social media. • After a baseline week, 88 TikTok users switched to a less personalized feed for one week. • During the less personalized week, daily frequency and duration of TikTok use decreased. • TikTok use was perceived as more controlled, yet less enjoyable. Social media platforms increasingly use algorithmic personalization, raising concerns about potential uncontrolled usage. However, these concerns remain partly speculative as evidence for the effectiveness of algorithmic personalization in driving user engagement is limited. Therefore, the present study investigated how TikTok users’ behavior and experiences would change if their feeds were no longer personalized based on their interests. In this preregistered study, 88 TikTok users participated in a two-week within-subjects design: a baseline week (default highly personalized feed), followed by an experimental week (less personalized feed). Daily experiences were assessed through daily surveys, and objective TikTok usage data was obtained through screenshots. We found that both daily frequency and duration of TikTok use decreased, self-regulation increased, and participants derived less enjoyment from their use. These findings highlight the critical role of algorithmic personalization in sustaining user engagement and suggest that reducing feed personalization may be a promising, though currently limited, approach to address uncontrolled social media use.