Soa Aids Nederland This study aimed to identify demographic, intrinsic and extrinsic predictors of youth's online sexual information seeking. We used survey data from a large, representative sample of youth (12-24 years) in the Netherlands (N = 20,500). We focused on online sexual information seeking in general, and on two specific types of online sources: interactive user-generated content (UGC) and professional sexuality education content. Findings suggested that LGB youth and youth with more sexual knowledge were more likely to consult sexual information online, both via UGC and via professional websites about sex. Professional content specifically reaches female youth more than male youth, and is more likely to be consulted by youth with more sexual experience and sexual problems. Further, being male, having low sexual esteem and high sexual curiosity were linked to a higher use of interactive UGC. Finally, only communication with friends about sex, but not with parents or partners, nor the amount and appreciation of schoolbased sexuality education received, was related to a higher use of online sexual information seeking, notably expert sources of sexual information. Next to parents, school, and friends, online media provide an important source of information for youth to learn about sex