Katy Perry. Picture: Supplied

Katy Perry has become the first Twitter user to reach 100 million followers.

The 'Chained To The Rhythm' hitmaker has reached the milestone amount of fans on the social media site, followed by Justin Bieber, who has 96.7 million followers whilst Barack Obama (90.8 million), Taylor Swift (85.1 million) and Rihanna (74.1 million) placed third, fourth and fifth respectively.

To celebrate Katy's achievement, Twitter posted a video on their own official account of some of Katy's greatest tweets over the years.

They captioned it: "Today, we #WITNESS history. Congratulations @katyperry, the first to reach 100 million followers! #LoveKaty (sic)"

Meanwhile, Katy – who joined Twitter in February 2009 -thinks she is so popular on Twitter because she writes her own tweets.

She said: "I would say 90 per cent of my Tweets, I've just made them up and you can tell because many of them are misspelled and full of typos.

"But the other five per cent is work related or it's just to keep people in the know about where I'm playing or if I'm doing a show and I always get really confused."

However, Katy does like to step away from her phone and just unwind without social media from time time.

Asked if she replies to her fans on Twitter, she added: "Sometimes I do, I kind of do a lot more of it when I'm in the zone mode. Right now I'm in a relaxed, chilled vacationing zone, I've got my spanx on and I'm just taking a little break ...

"I think I have to find that balance between tweeting too much and plus I have so many followers that nobody really wants me to fill up their timeline."

Bang Showbiz