Optimize (EP)

Optimize (stylised in all caps) is the fifth EP by Japanese rock band Coldrain. Self-produced by the band's lead guitarist Ryo Yokochi, it was released on 24 October 2025. It is the band's first release on Century Media Records and Sony Music Japan after leaving longtime label Warner Music Japan.

While it's the band's first EP in four years since the lead single "Paradise (Kill the Silence)" (2021) from the band's seventh studio album Nonnegative (2022) was released as such; it is the band's first full proper EP in eleven years since Japanese exclusive Until the End (2014), marking Optimize as the band's first EP to be released worldwide upon release and the first release by the band to be fully rolled out internationally since their fourth studio album Vena (2015).

The EP was preceded by three singles; the lead single "Incomplete" on 20 March, acting as the first ever thing the band released on their new label, the second single "Chasing Shadows" was released on 6 August, while the EP's third and final single "Free Fall" was released on 26 September. Optimize received positive reviews by critics, and has been promoted by a World Tour that began in September 2025, set to conclude in September 2026.

Optimize serves as the longest ever gap between releases of original material from the band, while at five tracks, it is the band's shortest EP to date, tracking at a little over 18 minutes.