Olajide Olayinka Williams "JJ" Olatunji, better known as KSI, is an English YouTuber and rapper. He is a co-founder and member of the British YouTube group known as the Sidemen. He is also the co-owner of Prime Hydration, XIX Vodka and a restaurant chain known as Sides. KSI registered his main YouTube account in 2009 and built a following posting gaming-commentary videos of the FIFA video game series. His YouTube content has diversified to include vlog and comedy style videos. As of March 2021, he has over 34 million subscribers and over 8 billion video views across his two YouTube channels. KSI's 2020 debut studio album, Dissimulation, debuted at number 2 on the UK Albums Chart. His second studio album, All Over The Place, debuted at number 1. He has achieved fourteen top 40 singles on the UK Singles Chart, seven of them ending up in the Top 10 and five of them ending up in the Top 5.

Olajide Olatunji, better known by his stage name KSI, is a YouTube and social media sensation with over 22 million YouTube subscribers, primarily in the United Kingdom. He is well-known for his content on FIFA, soccer, music, and comedy.