Teen heartthrob Justin Bieber with his hordes of fans known of Beliebers has become the King of Twitter, topping fellow pop star Lady Gaga as the user with the most followers.

Data from TwitterCounter.com showed that the 18-year-old Canadian singer jumped into the lead with 33.33 million followers, topping Lady Gaga's 33.32 million and ending her two-and-a-half year rule of the microblogging site.

A spokesman from TwitterCounter.com said Lady Gaga has held the top slot on Twitter since August 2010 when she overtook US pop star Britney Spears.

Bieber rose to fame as a baby-faced pop star singing love songs such as Baby after being discovered on YouTube in 2008.

He has released two No. 1 albums in the past 18 months - the holiday-themed Under the Mistletoe and Believe.

Bieber was named by Forbes magazine in 2012 as the third-most powerful celebrity in the world and his huge following on Twitter was cited as a reason why marketers need to take notice of the 140-character micro-blogging site.

Lady Gaga has dropped to second in Twitter followed by  singer Katy Perry in third with 31.49 million followers then Rihanna and Barack Obama with 26.17 million followers. Britney Spears has slipped to sixth place.

- © Fairfax NZ News