Katy Perry is set to make an epic performance today, closing out the 2013 iTunes Festival on Sept. 30.

Perry is set to hit the stage and perform several new songs off her upcoming fourth studio album Prism. The album is scheduled to be released on October 22.

"You can see me LIVE from London at #iTunesFestival! @iconapop and @iggyazalea open starting at 7:30p GMT Sept 30th!" Perry tweeted to her fans.

Without going across the pond, fans can watch the concert online for free through live streaming video.

Watch the iTunes Festival Live Stream.

Each headlining act is scheduled to perform at 9:00 p.m. London time, which translates to 4 p.m. ET. 

The festival kicked off on Sept. 1 with Lady Gaga. This month huge music stars likeElton John, The Pixies, Kings of Leon, Queens of the Stone Age and Robin Thicke took the stage.

You can watch on your computer at the iTunes store, Apple TV users can watch in HD from the main page or you can download the iTunes Festival app to your phone or iPad. If you miss it, many acts can be viewed for a limited time after the concert, and of course, iTunes will be selling some of the performances at the iTunes store.