Around 20 million children experienced sexual exploitation or abuse online in a single year across 21 countries, according to a UNICEF study published on Thursday. That is roughly one in five internet-using children aged 12 to 17 in the countries surveyed.

The findings come from “Through Children’s Eyes: How Digital Technologies Enable Child Sexual Abuse”, produced under the Disrupting Harm project that UNICEF runs with ECPAT International and INTERPOL, and were reported by Reuters. UNICEF calls it one of the largest studies of its kind.

The methodology is what gives the number weight. Researchers ran nationally representative surveys of about 21,000 internet-using children across Africa, Asia, Latin America and Eastern Europe between 2020 and 2025, alongside 100 in-depth interviews with survivors.

Breaking the estimate down, more than 15 million children were exposed to unwanted sexual material, more than nine million were pressured into sexual conversations or into sharing images, and four million had intimate images shared without their consent. The categories overlap, since a child can experience more than one.

Almost 60% of the incidents happened on social media, with Facebook, Instagram, Snapchat, TikTok and WhatsApp named in the study. Another 14% took place in online games.