What's Katy Perry's favorite day of the week!? Well, Friday apparently! The brunette songstress paid tribute to Rebecca Black's catchy song, Friday this past week during her concert in Australia!

Even if your a bit sick of RB's version of this auto-tuned song -- you have to check out Katy's version, because it's actually pretty darn good! We adore! Check out the video below and let us know what you think!

In a acoustic version that was accompanied by a guitar and slowed down a bit, Katy rocked out to the Youtube hit, causing the audience to go wild as they sang along! Pretty hilarious! At the end of the performance Katy commented on the tune, "I am so glad someone wrote a song about Friday!"

Katy Perry Covers Friday - Hollywire

Miss Perry has been extremely busy as she is currently on tour in Aussie land, while making her rounds the singer has covered quite a few songs including,  Willow Smith's Whip My Hair! Amazing!

What song would you love to see Katy Perry cover next!?