In January 2017, Karol G joined the reality talent show Pequeños Gigantes USA as a judge, offering advice to children 6–11 years of age who perform on the show. In May of that year, her collaboration with Puerto Rican trap artist Bad Bunny on "Ahora Me Llama" became regarded as her breakthrough hit. The video garnered more than 756 million views on YouTube and reached number 10 on the Billboard Hot Latin Songs chart. The song was described by Marty Preciado of NPR as a "bass-heavy, unapologetic trap anthem to the power of femininity, soiled in hi-hats and heavy sub-bass [that] challenges hegemonic masculinity, singing about respect, love and sex-positive decisions." According to Ecleen Luzmila Caraballo of Rolling Stone, "it was then that Giraldo joined the increasingly-global pop urbano wave and established herself as one of its most standout acts". "Ahora Me Llama" was listed on "Alt.Latino's Favorites: The Songs Of 2017" as one of the best Latin songs of 2017.
"Ahora Me Llama" served as the lead single for her debut studio album, Unstoppable, which was released in October 2017 and debuted at number two on the Billboard Top Latin Albums chart. Thom Jurek of Allmusic called Unstoppable "the first solid entry by a woman in the Latin trap movement". In March 2018, the singer released the jungle-inspired music video for her single "Pineapple". In that same month, she was announced as a finalist for the Billboard Latin Music Awards top female artist of the year. Later in 2018, she released the singles "Culpables", featuring Puerto Rican rapper Anuel AA, and "Mi Cama". "Culpables" peaked at number eight on the Billboard Hot Latin songs, while the remix of "Mi Cama" featuring J Balvin and Nicky Jam peaked at number six on the same chart.