Olajide “JJ” Olatunji (born 19 June 1993), also known asKSIOlajideBT or simply KSI, is a YouTube personality and a member of the Sidemen.
He was also active in Save the Children and prostate cancer charity promotions. KSI is possibly the most well-known of the Sidemen. His main YouTube channel has surpassed one billion video views and has gained more than eight million subscribers. He is best known for his gaming videos (particularly FIFA) and his comedic sketch videos. KSI recently became the face of Sport Relief online in 2014.