Reinhart began writing songs in Middle School, and she explains that "when I give myself the time to sit down, and reflect, and feel, and let things come out, I find that it’s very easy for me to do." Reinhart also fronted a band during college under such tentative names as Haley's Comet and Reinhart & the Rastatutes; the band covered classic rock songs from Led Zeppelin and other famous artists of the time.Reinhart first auditioned for the ninth season of American Idol, in Chicago, but did not advance to the Hollywood round.Every video reached the milestone in less than a month.Her performance of "Rolling in the Deep" reached over 2.4 million views before it was taken down, and now, after several removals and re-uploads, the most popular version has reached nearly half a million views.Reinhart supported the album with a 2017 fall US headlining solo tour.When she was nine years old, Reinhart sang Le Ann Rimes' 1996 arrangement of Bill Mack's 1958 classic, "Blue", on a big stage at a tattoo convention, and she was met with "overwhelming" support from the audience.In addition, Reinhart appeared twice on Billboard's list of "American Idol's Top 100 Live Performances." She was listed at number 68 for her interpretation of "Bennie and the Jets" and peaked on the list at number 18 for her cover of "The House of the Rising Sun." Additionally, Reinhart was ranked 26 out of 168 on Vulture.com's comprehensive list ranking all of the American Idol finalists from worst to best based on over-all performance within the scope of their respective seasons.
She reprised the role as a main cast member in the series' second season, which was released May 30, 2017.The album's lead single, "Baby It's You" was released June 16, 2017, followed by "The Letter" on July 13, 2017, and "For What It's Worth" on August 11, 2017."Let's Start," one of three original songs on the album, was released as the fourth single on September 15, 2017.Slezak crowned her TVLine's favorite Season 10 contestant and thanked her for "kicking ass" and being "a risk-taker and awesome".In less than a week, it garnered more responses than any other article on the site.In July 2011, Reinhart signed a recording deal with Interscope Records.and she subsequently became the first American Idol alumna to perform at Lollapalooza.Her second studio album, Better, served as an expansion of an initially conceived EP and was released on April 29, 2016, following the lead single and title track, "Better," which was released on April 8.She supported the release of the album with a 2016 summer headlining tour that was held throughout the United States and a spring leg that was held throughout Europe in May and June 2017. , was released September 22, 2017 through Concord Records.She sang "Bennie and the Jets" for her farewell encore performance.Although often harshly criticized by the judges for her song choice and stage presence, she was considered a fan-favorite and a dark horse in the competition.