Mood Ring (Britney Spears song)

"Mood Ring" (also known as "Mood Ring (By Demand)" upon its 2020 international release) is a song recorded by American singer Britney Spears for her ninth studio album, Glory (2016). It was written by Dijon McFarlane, Nicholas Audino, Te Whiti Warbrick, Lewis Hughes, Jon Asher, and Melanie Fontana. The "electro-tinged" R&B song was produced by DJ Mustard and co-produced by Twice as Nice, with vocal production provided by Asher.

Originally appearing as a bonus track for the Japanese edition upon its parental album release on September 14, 2016, "Mood Ring" was later included on the 2020 standard edition of Glory as the thirteenth track, which released on May 29, 2020 following a sudden resurgence in popularity of the album earlier that month. The track sold 13,300 copies during its first week of availability in the United States. It received a remix extended play treatment on June 26, 2020. Later, Sony Music issued the song to radio airplay in Italy as the lead single from the 2020 reissues and overall third single from Glory on July 10, 2020, almost four years after the album's release.