"Till the World Ends" is a song performed by Britney Spears. A remix entitled "The Femme Fatale Remix" was released that features Nicki Minaj and Ke$ha. It serves as the opening track on Spears' seventh studio album, Femme Fatale.
In February 2011, Ke$ha talked about the track in an interview with Spin:
That song is me imagining her and any female musician touring the world. You know, when you got out, and you're having an amazing, magical night and you don't want to go to sleep and you want it to last until the world ends.
In March 2011, Ke$ha talked about the track in an interview with MTV:
I consider myself a songwriter before and above everything else, so it’s an honor to write for one of pop music’s biggest icons. And I hope it gets everyone’s ass on the dance floor 'cause y’all know that’s what K-Money does best!
In March 2011, Spears talked about the track in an interview with Ryan Seacrest:
‘Till the World Ends’ is fun! It’s fun. I like it. It’s good energy. I’m a vibe person, and I think I love good-mood songs, and if it puts me in a good mood, it clicks for me.
In July 2011, Ke$ha talked about the track in an interview with Digital Spy:
I didn't get to see her record the track, but I have met her and she's super sweet. She's the queen of pop music, so it was quite a compliment that she wanted to record it. For her to then put it out as a single is fucking amazing. That song was written specifically for Britney - I put my brain in Britney Spears land and wrote that whole song for her.
A remixed version of "Till the World Ends", featuring Ke$ha and rapper Nicki Minaj, was leaked online on April 22, 2011. The same day, three countdowns with lines of the song appeared on the official websites of Spears, Ke$ha and Minaj; "sicker than the remix" from Spears, "if you feel it let it happen" from Minaj, and "next one on my hitlist" from Ke$ha. The Femme Fatale Remix was released on iTunes on April 25, 2011.