As of January 23, 2016, the most viewed video on YouTube is Gangnam Style by Psy, which has over 2.5 billion views. Gangnam Style was also the first video to reach 1 billion views, and the only one with at least 2 billion. At a distant second is Blank Space by Taylor Swift, which has 1.4 billion views.
There are 19 videos with at least 1 billion views, 17 of which are music videos. The video to reach the 1 billion mark in the shortest time is Hello by Adele, achieving the milestone in just 88 days. Gangnam Style was the second-fastest, taking nearly twice as long at 160 days.