Groff's roots in theater and acting began at an early age. When he was three years old, Groff fell in love with Julie Andrews' performance as Mary Poppins, and growing up, he and his brother put on childhood home productions, such as a performance of "The Wizard of Oz" in his father's barn, where he played Dorothy. Groff credits Sutton Foster as one of his greatest influences and idols, and as a young aspiring actor, he would wait at the stage door after her performances to get her autograph. Groff joined his middle school and high school drama departments, and it was there that he became inspired to start a career in theater.