Olajide Olayinka Williams “JJ” Olatunji (born June 19, 1993), better known as KSI, is a British YouTube star, rapper, boxer, actor and co-founder of the entertainment collective known as the Sidemen.

He was born and raised in Watford, Hertfordshire, England. His main channel, “KSI,” is now his official artist channel. KSI is short for his YouTube channel name KSIOlajideBT, which derives from “KSI” (a Halo clan), also meaning knowledge, strength, and integrity, his name, and “BT,” meaning “British Telecom.”

KSI started doing YouTube in 2010 and has now grown to be one of the most subscribed YouTubers in the world. Apart from being a YouTube sensation, he has also become an artist. Back in the day when KSI started doing YouTube, he was already making songs in his videos. The first song was his Call of Duty 1v5 Rap. At the time, he had only 50 subscribers.

Haven written and produced a wide majority of comedy rap songs from the span of 2011, on March 23, 2015, KSI released his debut single, “Lamborghini” featuring P Money. This song would launch an instant success and a kickoff to KSI’s musical career, as this song landed #30 on the UK Singles Charts. That same year, KSI would go on to release the single “Keep Up” featuring Jme. The following year, KSI would go on to sign with Island Records and release the Keep Up EP, which contains the previously mentioned single, alongside the official remix of “Lamborghini” with Scrufizzer, Youngs Teflon, and Sway.

Then on October 28, 2016, KSI would release his second EP, Jump Around, which contained the self-titled single featuring Waka Flocka Flame, as well as the standout singles “Touch Down” with Stefflon Don, which the single would end up in the 2017 film Baywatch, and “Friends With Benefits (FWB)” with MNDM, all of which would gain their own success through social media.

After had “blacking out” his whole social media accounts and disappearing for four months, on June 23, 2017, KSI released the single “Creature,” his first release after his long hiatus. This would lead up to the release of his third EP, Space, on June 30, 2017. This would also mark KSI’s first independent release instead of being released through Island Records. That same year, three months after the release of Space, KSI would release his fourth EP, titled Disstracktions. The EP would consists of diss tracks that he released during his comeback, alongside two original songs that weren’t released at the time.

2018 would be a quiet year for KSI, as that year would mark his transitioning into boxing. He would release four new singles, two of which would be the standout for his boxing career, “Uncontrollable” featuring Big Zuu, and “On Point,” a diss track aimed towards internet celebrity, Logan Paul.

Entering into 2019, on April 12, KSI and Randolph released their collaborative album New Age, the name resembling how they are creating a new style of music, which is portrayed through the different styles of beats used for the tracks. The album features guest appearances from Talia Mar, JME, and Quadeca. That same year in November, KSI signed a deal with RBC Records and BMG “take [his] music to the next level” and “further develop his music career in the US and internationally.”

On May 22, 2020, KSI dropped his debut solo studio album, titled Dissimulation. The album explored JJ’s own inner self and conflict with not just himself, but those around him, something he has said he found difficult exploring. The album features guest appearances from Offset from the hip-hop trio Migos, Smokepurpp, Lil Pump, Swarmz, Tion Wayne, Jeremih, Trippie Redd, Aiyana-Lee, S-X, Lil Baby, and Rick Ross. Three days later, on 25 May 2020, KSI dropped the deluxe with additional guest appearances from AJ Tracey, Rich the Kid, Randolph, and Crypt.

After having a successful year, entering into 2021, KSI would announce on Twitter that he would be creating his own record label, named The Online Takeover, in partnership with his music manager, Mams Taylor. He would soon sign American-British singer, Aiyana-Lee as the first signee to his record label. Then on July 16, 2021, KSI would release his sophomore solo studio album, All Over The Place. With features from artists like S-X, 21 Savage, Future, Lil Durk, Rico Love, Polo G, YUNGBLUD, and much more. This project peaked at #1 on the Official UK Charts on 29th July and stayed in the top 100 for 26 weeks. A month later, on August 27, 2021, he released the deluxe version, though 3 weeks before he released “Lose” featuring Lil Wayne, which earned JJ his first-ever entry in the Billboard Top 100, debuting at #86.

Entering into 2022, KSI would release his first single of the year “Locked Out” with S-X, kicking off the rollout for KSI’s upcoming third studio album. Then on May 13, 2022, KSI announced that he and Proper Loud had signed Yxng Dave to his record label as the second signee. After had being signed to RBC Records for two years, on May 30, 2022, KSI was officially signed to Atlantic Records, following his huge collaboration with Anne-Marie on the song “Don’t Play” with Digital Farm Animals, which the song would gain commercial success through social media.

After had releasing a couple more singles to wrap up 2022, January would begin with KSI collaborating with Oliver Tree on the song “Voices.” Then on May 13, 2023, KSI would release the track “Eazy” with Bugzy Malone and R3HAB, which served as KSI’s ring walk tune in his bout against Joe Fournier on the same night. KSI is expected to release his third studio album, Caught In Two Minds that year.