The Femme Fatale Remix of the song, featuring rapper Nicki Minaj and Kesha, was released on April 25, 2011. The remix adds a rap by Minaj at the beginning, new vocals by Kesha and a dubstep breakdown. The Femme Fatale Remix received mixed reviews from critics, with some complimenting the diversity of the group and Minaj's rap, while others criticized the addition of Kesha. "Till the World Ends" became a commercial success, charting within the top twenty in many countries worldwide, while peaking inside the top ten in nations such as Australia, Canada, France, New Zealand and the United States. The Femme Fatale Remix propelled the single to the top five in Canada and the United States. An accompanying music video for the song was released on April 6, 2011. Directed by Ray Kay, it portrays Spears in an underground dance party set on December 21, 2012. Critics noted the similarities with the music video for "I'm a Slave 4 U" (2001), and predominantly gave positive reviews for it. A choreography cut was released on April 15, 2011. Spears has performed "Till the World Ends" on television shows Good Morning America and Jimmy Kimmel Live!, and she performed the song with Minaj at the 2011 Billboard Music Awards.
Britney Spears "Till The World Ends" Song
In an interview with Spin on February 11, 2011, Kesha announced she had co-written a song with Dr. Luke and Max Martin titled "Till the World Ends" for Femme Fatale. She explained that the song was inspired by "me imagining [Spears] and any female musician touring the world", adding that "when you got [sic] 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." On March 2, 2011, the single's cover art, in which Spears appears sitting on a couch in a sweater and heels, was posted at Deezer.com. This was followed by a 30-second snippet of the song, which appeared at Amazon.de. "Till the World Ends" leaked online on March 3, 2011, which prompted Spears to post hours later on her Twitter account, "Looks like the cat's out of the bag..." She formally premiered the single at On Air with Ryan Seacrest, on March 4, 2011, at 10:00 EST (15:00 UTC). "Till the World Ends" was made available on iTunes the same day, several days earlier than originally planned. Following the announcement, Kesha spoke to MTV News stating that "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." During an interview with Seacrest, Spears described "Till the World Ends" as "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."
"Till the World Ends" is an uptempo dance-pop and electropop song, with an electro beat and elements of trance and Eurodance. The song opens with sirens and a "sizzling" bassline. Spears delivers confident and breathy vocals, in lyrics such as "If you want this good shit / Sicker than the remix / Baby let me blow your mind tonight." In the chorus, the song slows down while Spears sings "I can't take it take it take no more / Never felt like felt like this before / Come on get me get me on the floor / DJ what you what you waiting for?". The 4:3 cross-rhythm of the melody continues into a chant-like segment, in which "whoa-oh-oh-oh" is repeated. The bit was compared by Scott Shettler of AOL to the "rapid word repetition" of Kesha. Gerrick Kennedy of the Los Angeles Times stated that like her previous single "Hold It Against Me", "Spears's main intention with her new single seems to be keeping the dance floor pulsating with sweaty bodies". Jason Lipshutz of Billboard said the song recalls past hits by Taio Cruz, Robyn and Enrique Iglesias. Allison Stewart of The Washington Post felt the song was comparable to Iglesias' "Tonight (I'm Lovin' You)" (2010). According to the sheet music published at Musicnotes.com by Kobalt Music Publishing Inc., "Till the World Ends" is set in the compound meter time signature, with a moderate dance beat infused metronome of 132 beats per minute. It is composed in the key of C minor with Spears' vocals ranging from the low-key of Bb3 to the high-note of C5. Lyrically, the song talks about dancing until the end of the world
Bill Lamb of About.com commented that the song would "sound solid on the radio and bring crowds to the dance floor," but when compared to "Hold It Against Me", it was much more safe and not as innovative. Jed Gottlieb of the Boston Herald gave the song a B+, saying that "pop fans always need a huge hook, catchy chorus and break-it-down-build-it-up bridge. This song’s got all three". Edna Gundersen of USA Today called it "a sleek and impossibly catchy slab", and said that although the song is unmistakable Luke, Spears "holds her own with confident, kittenish vocals." Allison Stewart of The Washington Post stated the track "is Spears's most joyously danceable track in a long time." Sal Cinquemani of Slant Magazine compared to Kesha's "Blow" (2011), saying that the tracks "[are] so similar [...] that I can't decide which one I like more—or if I even like them at all." Popjustice also compared it to "Blow", but said "Till the World Ends" was not as good.
Caryn Ganz of Spin named it "her first truly synapse-sizzling single since 'Toxic.'" Kevin Ritchie of Now stated that "Wannabe World Cup anthem Till The World Ends kicks things off with an aura of pounding, Euro dance euphoria." David Buchanan of Consequence of Sound commented that "Till the World Ends", "Hold It Against Me" and "Inside Out" "simultaneously send Spears back to basics vocally, and into 2011 sonically." Rudy Klapper of Sputnikmusic said that the song "throbs with trance-y synths, a thumping electro beat that is pure sex and a chorus that goes and goes as only the best club hits can do, sensible lyrics be damned." Evan Sawdey of Popmatters said that "Till the World Ends" sets the pace of Femme Fatale, while calling it "a stadium-rocking pop anthem." Andy Gill of The Independent selected the song along with "Criminal" as the download picks of the album. Keith Caulfield of Billboard criticized the song's lyrics, saying they have "been echoed incessantly over the past year in countless Hot 100 top ten hits: dance until you drop from exhaustion." The chorus, he commented, "comes on hard like its the sexy spawn of Usher's 'OMG' and Baltimora's 'Tarzan Boy"
A remixed version of "Till the World Ends", featuring Kesha 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, Kesha and Minaj. The Femme Fatale Remix was released on iTunes on April 25, 2011. The same day, Spears uploaded a picture of the cover art to her Twitter account. Kesha told MTV News, "I'm a massive fan of both the ladies I share the track with. I wrote 'TTWE' for Britney [...] and she killed it and I loved it, but I just thought a supergroup of three hot, strong women could just take over the airwaves." The remix adds heavier bass during the beginning, and starts with Minaj rapping with intensity about a female hater, in lines such as "Told you they'd revive your career, but somebody lied/ I ain't talkin' poultry when I say this chicken's fried." This continues by Spears singing the first verse, after which Minaj says "It's Britney, bitch. I'm Nicki Minaj and that's Kesha!", and the first chorus is sung by the latter. Spears continues with the song and is accompanied by Kesha towards the end of the second verse and the bridge. The remix also features a dubstep breakdown, reminiscent of "Hold It Against Me".