About Flux

"Flux" is a song by English singer Ellie Goulding, released on 1 March 2019. The song was written by Goulding, Jim Eliot and Joe Kearns. It was included on Goulding's fourth studio album, Brightest Blue (2020). In an interview with The Guardian on New Year's Day 2019, Goulding announced that her fourth album would be released in 2019. She also talked about three songs named "Flux", "Love I'm Given" and "Electricity". According to her, "Flux" is "about the person who you almost ended up with". On 21 February, she took to social media to announce the single by posting its cover art and the release date of the track. The following week she shared further details regarding the song, including lyrics and a still from the music video.

"Flux" is a piano ballad, with pop influences. It is written in the key of C major and has a tempo of 93 beats per minute in common time. Goulding posted a silent teaser of the music video hours prior to its release. The accompanying music video premiered on YouTube on 1 March 2019, alongside the song's official release on all platforms. Shot entirely in black and white, the video depicts Goulding inside a dark hall playing a piano as rain pours on her. The video ends as a soaked Goulding stares gloomily at the camera as the rain continues.