. We explored the link between boys' pubertal timing and offline and online romantic and sexual activities using a sample of 142 Swedish early adolescent boys. Boys reported on two aspects of pubertal timing, a stage-normative (measured by five indicators of physical development related to puberty) and a peer-normative, and on offline and online romantic and sexual activities. Both aspects of pubertal timing was related to being romantically and sexually active offline, but only the stage-normative measure was linked to corresponding activities online. Thus, the implications of stage-normative pubertal timing on sexual activities seem to extend to online contexts.