Jessie J was born on March 27, 1988 in Chadwell Heath, Essex, England as Jessica Ellen Cornish.

She was cast in Andrew Lloyd Webber 's West End production "Whistle Down the Wind". She has two older sisters. Her mother was a nursery school teacher and her father was a social worker. She is the youngest of three children. When she was 17, she wrote her first song called "Big White Room". The song was inspired by real life experience. At age 16, she began studying at the BRIT School. At age 17, she joined a girl group called "Soul Deep". Ranked #55 in the 2011 FHM list of "100 Sexiest Women in the World". Diagnosed with arrhythmia [1999]. When she was 18 years old, she suffered a minor stroke [2005]. Performed in the Closing Ceremonies of the 2012 London Summer Olympics. She co wrote Miley Cyrus's song, "Party in the USA". Some of her music inspirations include, Lady Gaga, Katy Perry and Pink. She calls her fans, "heartbeats" ever since she went on her Heartbeat Tour.