Fact | Detail |
Full Name | Olajide Olayinka Williams Olatunji |
Nickname | KSI (Knowledge, Strength, Integrity) |
Date of Birth | June 19, 1993 |
Place of Birth | Watford, Hertfordshire, England |
Nationality | British |
Ethnicity | Nigerian (Yoruba) descent |
Education | Berkhamsted School |
YouTube Debut | 2009 |
YouTube Channels | @KSI, @JJ Olatunji |
Subscribers | 20+ million (main channel) |
Boxing Debut | August 25, 2018 |
Profession | YouTuber, Rapper, Boxer, Actor |
Music Debut | 2015 (with “Lamborghini”) |
Music Label | RBC Records & BMG |
Acting Debut | Laid in America (2016) |
Net Worth (2025) | Estimated $27 million |
Business Ventures | Prime Hydration, XIX Vodka, Sidemen Merch |
Group Affiliation | Sidemen |
Relationship Status | Previously dated Seana Cuthbert |
Social Media | Active on YouTube, Instagram, Twitter |
Olajide Olayinka Williams Olatunji, popularly known as KSI, was born on June 19, 1993, in Watford, England, to Nigerian immigrant parents. He was raised alongside his younger brother, Deji Olatunji, who also became a successful YouTuber.
KSI attended Berkhamsted School, a prestigious private institution, where he met future collaborators and fellow Sidemen members. Even at a young age, KSI showed signs of a charismatic entertainer, excelling in humor, video editing, and public speaking.
His pseudonym “KSI” stands for Knowledge, Strength, Integrity, values he holds in high regard. What started as a teenager’s gaming channel quickly became a media empire.
KSI’s rise to fame began on YouTube in 2009, where he uploaded FIFA gameplay videos and humorous commentary. His energetic personality and unique content attracted millions of subscribers, leading him to become one of the most influential YouTubers in the UK.
KSI made his acting debut in “Laid in America”, a teen comedy film released in 2016. He played the role of Duncan, a high school senior exploring wild adventures in the U.S. Though reviews were mixed, the film showcased KSI’s ambition to branch into mainstream entertainment.
Parallel to acting, KSI pursued a music career. His 2020 debut album “Dissimulation” peaked at number 2 on the UK Albums Chart. Later, “All Over the Place” (2021) solidified his status as a serious artist, featuring collaborations with Lil Wayne, Future, and Anne-Marie.
KSI has always kept his personal life relatively private. He was in a long-term relationship with Seana Cuthbert, but they parted ways around 2014. Since then, he has been linked with other partners, though he avoids sharing much about his romantic life publicly.
KSI has spoken openly about his struggles with mental health, emphasizing the importance of therapy and self-awareness, especially for men. He is also known for his close-knit bond with the Sidemen, a group of friends and creators who function as his extended family.
Though KSI has largely avoided legal scandals, he has faced public controversies:
From a financial standpoint, KSI has faced criticism over business transparency in ventures like Prime Hydration, co-owned with Logan Paul. However, the brand has achieved immense commercial success.
KSI networth in 2025 is estimated at around $27 million, stemming from a wide range of income sources:
His financial portfolio continues to diversify, proving he’s more than just a digital content creator.
KSI’s journey from a teen gamer to a multifaceted global celebrity is nothing short of inspirational. Through resilience, innovation, and bold career moves, he has created a legacy that spans platforms and industries. His biography reflects the evolution of digital fame—from humble vlogs to multimillion-dollar enterprises. As he continues to dominate in music, boxing, and entrepreneurship, KSI proves that versatility, integrity, and persistence are the true keys to lasting success.