Passing the milestone sometime over the weekend, Bieber also broke the record previously set by Lady GaGa. Back in October 2010, the "You and I" songstress was named the first artist to hit 1 billion mark on YouTube.
In another popularity showdown, Bieber could not top GaGa when it comes to Twitter followers. With nearly 14 million followers, Selena Gomez's boyfriend is still placed behind the Mother Monster who has more than 15 million fans subscribing to her official account on the micro-blogging site.
Bieber himself has not commented on his 2 billion mark on YouTube. In the last few hours, the teen pop idol has posted a series of tweets to promote his Christmas album "Under the Mistletoe" which is due November 1.