Sebert was born in San Fernando Valley of Los Angeles, California to a single parent. Her mother, Pebe Sebert, also a singer-songwriter, was struggling to get by and support Kesha and her older brother at the time, she would often look after then infant Kesha onstage while performing. Pebe moved the family to Nashville in 1991 after securing a publishing deal and Kesha spent the rest of her early years there, attending a music school in the countryside. Pebe often brought Kesha along to recording studios and encouraged her to sing, Kesha was exposed to the music many country music artists while learning to write songs. The Sebert family was featured in an episode of The Simple Life as the host family which led to an incident later on where Sebert vomited in Paris Hilton's closet while at Hilton's house and was subsequently removed from the compounds. Her best friends are kelly dermody and allie schmitt At the age of seventeen she dropped out of Brentwood High School in Brentwood to return to Los Angeles to pursue a music career.
She decided that she wanted Prince to produce her music, so she found and snuck into his Beverly Hills home. Once she was discovered, she was promptly thrown out, but not before she dropped off her demo, which was wrapped in a purple bow, with Prince himself. Sebert survived on low income and few gigs while pursuing her career at first, moonlighting as a waitress to make ends meet while furthering her music career in studios with different producers. It was then that she met Dr. Luke who had come across her demos and was so impressed that he contacted her with Max Martin and began a working relationship with her immediately.
Between 2006 and 2008, Sebert's music appeared in a variety of media, her song "Former Overexposed Blonde" appeared in Degrassi: The Next Generation, while "Backstabber" and "Chain Reaction" were used in The Hills. During this time, she also co-wrote The Veronicas' single, "This Love", sang background vocals for Britney Spears' song "Lace and Leather" and appeared in the video for Katy Perry's single, "I Kissed a Girl" Her appearance in the video arose due to her being friends with Perry, they met frequently as aspiring pop singers in Los Angeles and shared many musical collaborators. Sebert currently lives in a shared mansion in Laurel Canyon, Los Angeles.
She gained exposure in the mainstream media after being featured on Flo Rida's single, "Right Round". The collaboration came about when Flo Rida decided that the song needed a female voice, Sebert was then roped in for the part after being suggested by Dr. Luke, who was producing the song. Flo Rida liked the end result so much that he invited her to guest on another song, "Touch Me", for his album. Soon after, it was announced that she had signed with RCA Records through Dr. Luke and was working on her debut album, which has now been completed and is due to be released in early 2010. Her first single, "TiK ToK", was officially serviced to US radio on October 5, 2009. It features an uncredited cameo appearance by Diddy who is the inspiration for the song. Another song, "Boots and Boys" was used in an episode of the new Melrose Place. Sebert revealed in October in an interview with MTV Sweden for MTV Push that her debut album would be named Animal.
On March 27, 2009, she appeared onstage alongside 3OH!3 at one of their concerts at Avalon Hollywood to perform their duet, "My First Kiss". She also performed at that year's Lollapalooza as part of the BMI Stage. Sebert's musical credits in 2009 include work for Teen Cribs, she had previously done background cues for My Super Sweet 16 as well, co-writing the title song for Miley Cyrus' The Time of Our Lives EP and featured appearances on Pitbull and Taio Cruz's albums. Sebert has also been a supporting act of Calvin Harris on tour in the UK and has performed with Mickey Avalon on multiple tour dates.