Katy Perry has amassed 50 million followers on twitter.

The 'Roar' hitmaker reached the staggering milestone last week after adding a huge 18 million followers over the last 12 months, a feat which has seen her overcome Justin Bieber and Lady GaGa - who have 49.1 million and 41 million followers respectively - to become the most-followed person on the social networking website.

She tweeted at the weekend: ''What a raging Friday night! Made a sandwich. Watched The Business of Being Born. Hung out with a cat. #imagrownwomanicandowhateveriwant

''Oh yeah AND we grew to 50 million Katycats! Eh, regular day at the office.(sic)''

Katy used her social media power to urge her fans to follow boyfriend John Mayer following his return to the social networking website.

She wrote: ''FOLLOW FRIDAY @JohnMayer who's account has basically been in a coma state for a couple of years. Let's update him on all the cat youtubes he may have missed pls! Thanks!(sic)''

Meanwhile, the 'Gravity' hitmaker admitted he was unsure about returning to the website.

He tweeted: ''I used to RULE these hallways...

''I'll be honest, when it came to rejoining twitter, I had mixed emojis.(sic)''