Amber Josephine Liu (born September 18, 1992), known mononymously as Amber, is a Chinese-American singer, rapper, and songwriter. She debuted as a member of the South Korean girl group f(x) in September 2009. In 2015, she became the first f(x) member to make a solo debut with the release of her first extended play Beautiful and has since released solo singles.
In July 2018, she joined Steel Wool Entertainment following her original label SM Entertainment’s joint partnership with Steel Wool to manage her American activities. She later released the maxi singles "White Noise + Lost At Sea'" in September 2018 and "Countdown + Beautiful" in November 2018. In September 2019, she left SM Entertainment and exclusively signed with Steel Wool Entertainment prior to the release of her 2020 extended play X.