ABSTRACT This study examined how TikTok use relates to political engagement and aggression. Due to different imagined audiences , we expected TikTok use to be more strongly related with contentious political engagement than use of other social media platforms, such as Facebook and Twitter. In order to test these expectations, we conducted a survey with 700 U.S. adults. Results show that TikTok, Facebook, and Twitter use is positively related to online political engagement, but the nature of this engagement is very different. Facebook use is related to talking politics with friends and family, while TikTok use is related to talking with those who hold opposing views. Further, Facebook use is negatively related to agreeing that it is acceptable to be aggressive in political conversations, while TikTok use is positively related to believing that it is acceptable to be aggressive and to holding feelings of hatred for political opponents. Twitter use is unrelated to these outcome variables. These results suggest that TikTok users are more likely to partake in derisive and contentious political engagement.