As a teenager Henry worked as a youth reporter for the newspaper Göteborgs-Posten. Since 2005 she has been active on blogs such as Nöjesguiden, Devote and the magazine Veckorevyn. She started posting videos on YouTube in 2011, and in 2013 hosted a talk show on Kanal 5 where she interviewed guests and performed comedy sketches. In the spring of 2014, Henry starred in a second season of her talk show, this time entitled Häng med Clara Henry, where instead of sitting in a studio and talking, she met each of her guests and hung out for an entire day. She was named "Vloger of the Year" at Veckorevyn's Blog Awards 2013. Henry presented the Melodifestivalen 2014 pre-show and after-show talks, where she interviewed the winners of the semifinals and other guests on SVT. On 15 April 2014, she presented the Guldtuben-gala, for the online network, in which an award is given to Sweden's best YouTube star. At this gala Henry won an award for best vlog channel. Along with the comedian and TV personality William Spetz, Henry participated in the SVT comedy showValfeber, which satirized the upcoming 2014 general elections in Sweden. On 30 June 2015 Henry presented an episode of the Sveriges Radio showSommar i P1 in which she discussed her life. In September of the same year, Henry's first book, Ja jag har mens, hurså?, on the subject of "menstrual periods and why women should not be ashamed to talk about them", began to be distributed by the Swedish publishing house. After the book's release, Henry held a lecture tour themed YouTube på blodigt allvar in multiple cities across Sweden, namely Borås and Uppsala. In December 2015, Henry worked as a travelling reporter for radio-television campaign Musikhjälpen. Among other places, she went to the Philippines to meet families that had been affected by Typhoon Melor. On 30 September 2016, SVT announced that Henry would host all six shows of Melodifestivalen 2017 alongside David Lindgren and Hasse Andersson. In December 2016, Henry revealed that she is pansexual. She joined the reality showRobinson 2020 as a contestant in the middle of the season. She was chosen into team South before reaching the merger and eventually the top 3 final where she ended second, after Michael Björklund.