Choi Jong Hyun, better known by his stage name Chang Jo, is a South Korean dancer, singer, composer, choreographer, model and actor. He is best known as the vocalist, main dancer, rapper and maknae of the South Korean boy group Teen Top. He has a talent for Taekwondo (black belt). He wrote Up10tion's songs ''Never Ending'' and ''Party2nite''.
His contact with TOP Media ended on January 10, 2022 and he decided not to renew it
On June 7, 2023 it was announced that he has signed an exclusive contract with BEAT INTERACTIVE.