"X" is a song by American recording artist Chris Brown, taken from his sixth homonym studio album X (2014), and was released as an instant-gratification track alongside the album pre-order on iTunes on August 25, 2014.^[2] It was written by Brown, Diplo, Djemba Djemba, RoccStar, Dewain Whitmore and Sevyn Streeter. Musically, "X" is a song that unites R&B and soul vocals with a dance beat. The song contains lyrics about Brown forgetting a failed relationship with a woman. "X" received critical praise from music critics, which praised the maturity of the lyrics and his production. Following the release of X, as a result of the strong digital downloads, the song charted on multiple charts worldwide; it peaked at number 98 on the US Billboard Hot 100, number 26 on the US Hot R&B/Hip-Hop Songs chart, number 63 on the French Singles Chart, number 12 on the UK Singles R&B Chart, number 81 on the UK Singles Chart and number 75 on the Australian Singles Chart.

"X" is a song that unites R&B and soul vocals with an EDM beat, with an instrumentation provided by a roland TR-808 and synthesizers.^[3] In the song Brown sings over a soft beat before transitioning into a more up-tempo sound.^[4] In the song, Brown says that he's forgetting a failed relationship with a woman, as he sings, "I swear to god i'm moving on!", admitting his past errors singing "I deal with my pain like a lonely child".^[5] Music critics speculated that the lyrics were about Brown's former relationships with aspiring American model and fashion designer Karrueche Tran and Barbadian recording artist Rihanna.^[6]

"X" received critical praise from music critics. Miranda J. of XXL gave a positive review saying that in the song Brown "speaks of maturing and accepts his role in recent events, over the soft beat before transitioning into a more up-tempo sound".^[7] Brad Wete of Billboard called the song "Brown's most honest song", saying also that "it's safe to say that this is a man who knows he's got to get his life together and has to prove to himself and others".^[8] Slant Magazine's Alexa Camp felt that "X" was "an admirable attempt to take responsibility for his anger-management issues" from Brown, speculating that the lyrics were about Brown's relationship with Barbadian recording artist Rihanna.^[9] Marcus Dowling of HipHopDX wrote that "Brown emphatically stating that “[he] swears to god he’s moving on!” is either an amazing kiss-off to well documented on again/off again flame Rihanna, or an angry note to on again/off again mate Karrueche Tran".^[10]