Capsule, stylised as capsule on earlier releases and as CAPSULE from 2013, is a Japanese duo formed by Yasutaka Nakata (co-producer, art director, responsible for all lyrics and music) and Toshiko Koshijima (vocals). First formed in 1997, they would not debut until 2001, with their first single being released under Yamaha Music. In 2003, Yasutaka created his own label, Contemode, and has produced other artists on the label.

Though their debut album ハイカラ ガール fit into the adult contemporary genre, their 2nd album Cutie Cinema Replay pushed capsule into the Shibuya-kei sound, marked by samples and emulation of 1960s mod music. Their 7th album [m=1719166] marked a noticable shift towards electropop, gradually transforming into electro house by the time of their 10th album, 2008's [m=286439]. After the name capitalization change, CAPSULE released two albums before disappearing: one of downtempo and electronica (2013's [m=613158]) and one of big room EDM (2015's [m=829765]), both sizable shifts in the group's sound. After a multi-year hiatus, CAPSULE returned with 2022's [m=2902570], showcasing an entirely new synthwave / city pop sound.